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Pops & Clicks / IRQ troubleshooting, Windows 2000
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There are a variety of possible reasons why you could experience noise in your audio playback- or recording. Go through the following checklist and make sure that you've tried all these troubleshooting tips before walking through the rest of this guide.


-       Does you computer meet or exceed the Minimum System Requirements?

-       Do you have the latest driver installed for the M-Audio Delta ( at time of creation of this document)?

-       Are you sure that you installed the right driver for your Windows Version? (Go to the "About" tab in the Delta Control Panel. For Windows 2000, the Driver Version has to start with "5". Older, incompatible Windows 98 Drivers start with "4").

-       Make sure the M-Audio Delta is set to "Independent" in the "Hardware Settings" tab of the Delta Control Panel (then use the "Save" function).

-       Make sure Service Pack 4 (or higher) is installed.

-       Make sure you are using harddrives running at 7200 rpm or higher. Try to run a defragmentation to ensure the best performance of your harddrive. (Start/Programs/Accessories/System Tools/Disk Defragmenter).

-       Make sure you have enough space on your harddrive (500 MB or more) when beginning a new recording (usually 10 MB per minute of stereo audio).

-       Do you use a separate Harddrive dedicated to the Audio Data (with Windows running on another Harddrive)? This shouldn't be necessary, but we highly recommend this since it improves the overall performance.

-       Are your Harddrives set to "DMA if available"? Make sure they are. (Device Manager/IDE Controller/Advanced Settings)

-       Check if any other PCI card with high data throughput (e.g. SCSI cards or Graphics Accelerator Cards) are installed. If so, does the problem occur without the card installed? If not, is there a way to turn "PCI Bus Master" off for that card?

-       Do you have a Chipset by the brand "Via"? If so, certain chipset models may require the installation of a driver- or firmware update, available from http://www.viatech.com (e.g. Hyperion 4in1 update).

-       Are you using a RAID controller in your system? If yes, (especially applies to "Promise" RAID controllers) make sure the latest driver is installed. Also lower the "PCI Bus utilization" (see your mainboard's manual).

-       Do you use the S/PDIF (digital) input or output of your M-Audio Delta? If yes, make sure the device sending the signal is set to "Word Clock Master" and the receiving device is set to "Word Clock Slave"

-       Is it possible that the signal you are recording or playing back is so hot that it might overdrive the inputs or outputs of the M-Audio Delta? Check the "Variable Output Level" settings in the "Hardware Settings" tab of the Control Panel and make sure the settings match the external equipment you connect to your M-Audio Delta (most non high-end devices run on -10 db; HiFi and Home Stereo equipment is usually matched best when the Delta's variable signal levels are set to "Consumer"). If you still get clicks or distortion during playback, reduce the playback level. If you still get clicks or distortion while recording, reduce the level at the device that is sending audio to the M-Audio Delta.

-       If you experience humming or buzzing you probably have a "ground loop". Try connecting all devices to the same power outlet on the wall. Also check the Miscellaneous section on our FAQ page for more tips on how to troubleshoot ground loops.

-       Is your computer located close to a device with a strong magnetic or electric field (the computer monitor / speakers / refrigerator / cell phone, etc.)? Move the computer away from such devices.

-       Are you experiencing feedback? Make sure to use a headphone when recording through a microphone - don't monitor through speakers when recording with a microphone.

-       Could the noise you are recording be coming from another track already recorded or something that is plugged into your mixing desk? Check the routing on your mixing desk and in your software to verify you're only recording what you really want to record.

-       Do you get some type of Zipper noise when moving the mouse? Try to lower the Hardware Acceleration for your Graphics Card (Right click on desktop background/properties/settings/advanced/troubleshooting/set to none/ restart computer). If this helps, make sure the video card driver is compatible with the DirectX version you have installed on your computer.

-       Do you get some type of Zipper noise when using automation? This is due to the low resolution of 128 steps when using automation that is controlled by MIDI. Check if your software allows you to "interpolate" between the MIDI steps.

-       Does your playback sound out of phase or do you get an echo during the recording? Make sure you are only using one type of monitoring - either the Hardware Monitoring provided by the Delta Control Panel or the Software Monitoring provided by your recording software. Don't use both at the same time.

-       Do you get phasing when playing back tracks from the computer and also from external recorders at the same time? The synchronization isn't sample accurate. Make sure to distribute the tracks on the different devices so that there are no similar signals on different machines.

-       Is there a possibility that any crackling might be introduced due to bad cables or bad contact or faders on you mixing desk? Check if the crackling also appears when using devices other than the M-Audio Delta.

Make sure the noise problem you are experiencing is not due to any of the examples listed above. If you are sure, you probably have a resource conflict. The following text explains what that is and what you can do about it.

Pops and clicks due to resource conflicts / lack of resources:

Every Windows Computer only has a limited amount of physically present resources that it can assign to the different hardware devices that you install into your computer or attach to it. The most important type of these resources is called "IRQ" or "Interrupt Request". Your computer probably has only one CPU (central processing unit) which is the "work horse" in your computer. This CPU has to handle everything your computer does - from what will be displayed on your screen to what it will have to calculate for the software you are running and will also have to work on the audio you are sending to the M-Audio Delta outputs. (...and many, many other things!).

There needs to be an organization of how and when the different devices and components in your computer are allowed to "INTERRUPT" the CPU so it will stop doing whatever it is doing and will do this task instead. IRQs (interrupt requests) are numbers from 0 to 15 that organize the installed hardware in a hierarchy and allow them to interrupt the CPU and give it a new task.

All the music that you play back or record in your computer has to be processed by the computer's CPU. In a nutshell, it works something like this: Once the audio cards IRQ has been called up by the CPU, it will send a junk of music to the CPU for calculation. After the CPU is done with the necessary calculations, it will send junks of music back to the audio card before it moves on to working on something else (like graphic display etc.) The junks of music received by the audio card are temporarily stored in something called a "buffer" and will be read out from there to send the music to the audio card's outputs so you can hear it. If the audio card has to wait too long until it is allowed to interrupt the CPU again and send/receive it's next junk of music for the playback, the "buffer" will run out of temporarily stored music and the card won't have anything for the playback. If that happens, you will hear a popping sound or crackling until the CPU finally allows the audio card to send/receive the next junk of music to have something for the playback.

If your computer is fast enough and the M-Audio Delta audio card has a unique IRQ (interrupt request or better "interrupt permission") assigned to it that it doesn't have to share with anything else, everything should be fine and you shouldn't get any resource related pops and clicks. If you do get pops and clicks and your computer is not the fastest, you might need to increase the size of the buffer mentioned above. This is done by opening the Delta Control Panel, switching to the "Hardware Settings" tab and then increasing the value for "DMA buffer size".


If you have so many devices installed in your computer that it cannot assign an individual IRQ for every one of them, especially for the M-Audio Delta, your computer will assign the same IRQ to more than one device. Those devices will have to share the priority when interrupting the CPU and will have to "fight" about who can talk to the CPU first. Although the sharing of IRQs is OK with many non-audio devices, it can be a problem for audio cards. This will cause the audio card to not get as much music processed by the CPU as necessary and therefore you will get pops and clicks or even distortion. Let's find out if your computer assigned a unique IRQ to your M-Audio Delta:

1.     Click on "Start"

2.     Click on "Run"

3.     Type "msinfo32"

4.     Click "OK"

5.     Click on "Hardware Resources"

6.     Double-click on "IRQs"


You will see a list of devices installed in your computer and to the left of them you will see what IRQs have been assigned to them. Locate the M-Audio Delta card and check what IRQ it is on. Ideally, the M-Audio Delta is the only device on an IRQ lower than number 15. Even if that's the case, there are a number of special cases that need to be mentioned here:

1.     On many mainboards, IRQ 9 is internally shared with IRQ 2 although it won't show here that it is shared. If the Delta card is showing on IRQ 9, we probably need to fix this.

2.     On some systems, the Video or Graphics Cards are not displayed in this list. Typically the IRQ for this card is either number 10 or 11. If the M-Audio Delta is on IRQ number 10 or 11 but your Video card doesn't show, then there is a good chance you have those two cards conflicting.

In short, if the M-Audio Delta is on it's own IRQ below number 15, but not on IRQs 9, 10 or 11, everything is fine (although either 10 or 11 might also be OK, depending on what IRQ the Video Card is on).

Some IRQs are reserved for mandatory system devices and are always in use - no matter if they are listed here or not. Typically, these IRQs are the numbers 0, 1, 2, 6, 8, and 13. These IRQs can't be used for the M-Audio Delta nor any other device added to your PC.

If there is another device listed on the same IRQ as the M-Audio Delta (and below the number 15), this can mean two things - one of which is definitely a problem, the other might be one but doesn't have to be. It very much depends on which version of Windows has been installed on your computer and which "mode" it is running in:

1.     Standard PC: If you are running Windows 98 or ME, or if you are running Windows 2000 or XP in what is called "Standard PC Mode" (meaning that Windows won't even try to manage the assignment or sharing of IRQs), then a shared IRQ is a problem that needs to be fixed. You have an "IRQ conflict" which will cause problems and needs to be resolved.

7.     ACPI: If you are running Windows 2000 or XP in ACPI mode, shared IRQs are OK if Windows is doing a good job on the IRQ management. Sometimes Windows doesn't handle it too well though, so we might still have to tweak the system a bit to set this straight.

Let's look into what Standard PC versus ACPI is, how you can determine which mode your Computer is installed in and what you can do in both modes to get rid of pops & clicks:

Standard PC Mode in all Windows Versions:

All versions of Windows before Windows 2000 (e.g. Windows 95, 98 and Me) were only running in "Standard PC" mode. ACPI mode is not available for these systems. Windows 2000 and Windows XP can run in this "older" mode, which can be very helpful in certain situations. Windows' possibilities for the management of IRQs in Standard PC mode are very limited and dependent on certain hardware settings. If there is a IRQ conflict or an IRQ that is in use by more than one device, it is almost always a problem that needs to be fixed. Especially if the M-Audio Delta is sharing an IRQ with another device. Luckily, Standard PC mode allows us to tweak some settings outside of Windows that will allow us to force Windows to use certain IRQs. The first steps on the way to resolve IRQ conflicts for Standard PC mode and ACPI mode are the same, so please follow the instructions given further below.

ACPI Mode in Windows 2000 and Windows XP:

If the M-Audio Delta shows on an IRQ higher than number 15, this means that you are either running Windows 2000 or Windows XP. It also means that Windows has been installed in what is called "ACPI" or "Advanced Configuration and Power Interface" mode. Although more than 16 IRQs (0 to 15 is a total of 16, since the zero counts as a number in this case) are displayed, your computer's hardware still doesn't have any more physically available IRQs than 16. When running in "ACPI" mode, windows is actually managing the assignment of the physically available IRQs internally and won't even show you which physical IRQs it is really using. Instead, it will show "virtual IRQs" that can reach numbers up to the 20's or 30's, depending on what's installed on your computer. Although the M-Audio Delta might show on it's own "Virtual IRQ", it will most likely share a physical IRQ with another device underneath the surface and invisible to you.

If the M-Audio Delta is showing on the same IRQ with two or more other devices but below the IRQ number 15, this is also indicating that you are running Windows in ACPI mode. Windows simply decided to show the devices on the same IRQ and stay within low number instead of adding higher and higher virtual IRQ numbers. No matter which way Windows is handling the IRQ assignment - it should not be a problem, but sometimes it can be.

As we explained earlier, pops and clicks are caused if installed devices have to (in simple terms) "fight" for the attention of the CPU. Although ACPI mode doesn't clearly show us which device the M-Audio Delta has to "fight" with, the pops and clicks tell us that it does.

Understanding the concept of IRQs, you will probably think "Why don't we just manually assign an IRQ to the M-Audio Delta to ensure it's on it's own?" Unfortunately, ACPI mode in Windows 2000 and Windows XP doesn't allow this. Microsoft is so confident that Window's internal IRQ assignment can never go wrong, that they completely left out any possibility for troubleshooting. This means we have to use tricks to get this issue resolved.

For a start, we need to make sure that there are enough free resources available on your computer. The easiest way to do that, is to disable everything built in your computer that you are not actively using. This way, not so many devices have to fight for access to the CPU. Fortunately, there are a number of things in most computers that are activated by default, which you are probably not using.

Here's a list of typical devices installed on many computers with an explanation of which ones can be disabled if you are not using them (the IRQ information relates to "physical" IRQs. In ACPI mode, the devices might appear on any IRQ number and some of them might not even show up at all):

- System Timer (always IRQ 0):

Mandatory. Cannot be disabled or shared.

- Computer Keyboard (always IRQ 1):

Mandatory. Cannot be disabled or shared.

- Interrupt Controller (always IRQ 2):

Mandatory. Cannot be disabled or shared.

- Serial Port / Com Port 2 (usually on IRQ 3):

Can be disabled if you don't have anything connected to this port. This is the classic-style mouse port. Also, there are a few older digital cameras or scanners that might work on that port. Most likely you are not using this port and can disable it.

- Serial Port / Com Port 1 (usually on IRQ 4):

Can be disabled if you don't have anything connected to this port. See "Serial Port / Com Port 1" for more info.

- Onboard Soundcard (could appear on any available IRQ - often on IRQ 5):

We recommend that you disable any onboard soundcard or remove your old soundboard from the computer (if possible). This will help to free 1 to 3 IRQs (depending on the soundcard) and to avoid possible conflicts with other audio devices like the M-Audio Delta.

- Onboard Modem (could appear on any available IRQ):

Needed if you use the built in Modem to connect to the Internet via Dial-Up. If you have a Cable Modem, DSL, are connecting to the Internet through a gateway in the local network or aren't connecting to the Internet at all, you can disable the Modem.

- Floppy Disk Controller (always IRQ 6):

Needs to be active if you want to use the Floppy drive.

- Printer Port / LPT Port (always IRQ 7):

Needed if an older (non-USB) Printer is connected to your computer. Also, some Midi Interfaces can be used on this port. You can disable this port if you don't have anything connected to it.

- System CMOS / Real Time Clock (always IRQ 8):

Mandatory. Cannot be disabled or shared.

- USB Controller (could appear on any available IRQ - often on IRQ 9):

Needed if there is anything connected to your computer's USB port. Many modern computer peripherals connect to the USB port, so you most likely don't want to disable this port.

- Video Card (could appear on any available IRQ, but usually on IRQ 10 or 11):

Mandatory. Cannot be disabled, but is shared often times. If shared, this is very often the reason for the pops and clicks, since this card has a high data throughput. We explain this further below.

- Network Card / NIC adapter (could appear on any available IRQ):

Needed if you have a local network or if you are using a Cable Modem or DSL. If you don't network with other computers or have a dedicated Modem for your Internet connection, you can disable the Network card.

- PS/2 Port / Mouse (always on IRQ 12):

Needed if you are using a PS/2 mouse (round connector). If you are using a USB Mouse, you can disable this port.

- Numeric Data Processor (always on IRQ 13):

Mandatory. Cannot be disabled or shared.

- SCSI Controller (could appear on any available IRQ):

Needed if you have any SCSI Harddrives, CD-ROM drives or any other SCSI devices built in- or connected to your computer. You can disable the SCSI controller if you don't have any SCSI devices connected to it.

- RAID controller (could appear on any available IRQ):

This is a special kind of harddrive controller that usually cannot be disabled. Raid controllers can cause interference though and it might be necessary to adjust the PCI-Bus utilization. See the "Checklist" at the beginning of this guide).

- Primary Harddrive Controller (always on IRQ 14):

Needed to run Harddrives that connect to the IDE or E-IDE connector on your mainboard. Each IDE controller (primary and secondary) can control 2 IDE devices - typically harddrives or CD-ROM drives. Most mainboards have two harddrive controllers giving you the possibility to run up to 4 IDE devices at the same time. If you have only up to two IDE devices (e.g. a harddrive and a CD-ROM drive), you can connect them both to the same IDE controller and disable the Secondary IDE controller which will save you an IRQ. This is questionable though, since in some cases this might reduce the performance of your main harddrive. We only recommend to disable Harddrive Controllers for advanced users. If you know for sure that you are not using any IDE hard- or CD-ROM drives (e.g. if you are only using SCSI drives for everything), you can disable both, Primary- and Secondary IDE-Controllers.

- Secondary Harddrive Controller (always on IRQ 15):

See description for "Primary Harddrive Controllers".

Use the list printed above to determine which of the devices you are actively using and which you aren't. Note which devices you are NOT using, so we can disable them. There are two ways to disable hardware devices in your computer - through the Computers Bios (Setup) or through the Device Manager within Windows. It's much better and more reliable to disable the devices through the Computer's Bios (Setup). Besides, there might be one or more reserved IRQs in the Bios that are not available for Windows at all, so you might be able to provide more resources, simply by un-reserving these IRQs. The Bios (this is an acronym for "Basic Input Output System") is some type of a Mini-Operating System that is stored on an actual Chip on your computer's Mainboard. It's always there, even if you wouldn't have any harddrive installed in your computer. There are many different brands and types of Bios' that need to be accessed and configured in different ways. Therefore we can't explain how to do this for every one of them, and will have to concentrate on how to disable devices from the Device Manager. Generally though, you can access the Bios right after turning on the power of your computer. On custom built computers, you can usually access the Bios by pressing the "del" (delete) key right after powering on the computer.

If you have a brand name computer like Compaq, Dell, Gateway etc., you will probably first have to get rid of the Startup Screen that displays the brand name. In most cases, pressing the "esc" (escape) key will make this screen disappear. On some machines it might also be the Spacebar, F1 or F2. Most computers display which key you would have to press to get rid of this screen. Once you get past the brand name splash-screen (which must occur within about the first 10 seconds after powering-on), you will have to press another key to access the Bios (sometimes called "Setup" if displayed on screen at this point). Here is a list of typical keys to access the Bios for different computer brand names (some manufacturers change these keys with different models, so this might not be completely accurate):

-       Acer: F2

-       Compaq: F10

-       Dell: Delete or F2

-       Fujitsu: F2

-       IBM Aptiva: F1

-       IBM Thinkpad: F2

-       Gateway (older): combination of Ctrl, Alt and S

-       Gateway (newer): F1 or Delete

-       Hewlett Packard (HP): F1

-       Hitachi: combination of Ctrl, Alt and S

-       Packard Bell: F1

-       Sony: F2

-       Toshiba: Esc (or through DOS by typing c:>tsetup

What you are looking for in the Bios depends on the brand and model, but can usually be found in a Bios category like "Advanced" and "I/O Configuration" or "Chip Configuration" etc. In these categories you will find the activated devices and should have an option to set these devices to "disabled". You might need to consult the Computer's Manual or contact the Computer manufacturer for more details on how to disable devices from the Bios (Setup).

WARNING: Some Computer Manufacturer might void the warranty if you make changes in the computer's Bios! Please check with the manufacturer for details on their warranty policy.

Once you are done making the desired changes in the Bios, press "F10" to save the changes and then select "Yes" to verify saving the changes. If you don't want to save your changes, then repeatedly hit escape until your computer reboots (you might have to select "Yes" when "exit without saving" is displayed).

As mentioned earlier, we want to concentrate on how to disable devices through the Device Manager of your computer. This is not the most reliable way, but it should work fine in most cases and we can tell you exactly how to do this right here:

1.     Click on "Start"

2.     Click on "Settings"

3.     Click on "Control Panel"

4.     Double-click on "System"

5.     Click on the "Hardware" tab

6.     Click the "Device Manager" button.

The device manager lists all the devices that are installed in your computer in different categories. You can identify what's a category and what is an actual device by looking if there is a plus or minus next to the entry in this list. If there is a plus or a minus, it's a category. Clicking on a plus opens a category and displays the included devices. Clicking on a minus closes a category and hides the devices. The disabling of devices works in the same way for all the different devices installed in your computer. Here's an example of how to do this for the Computers Printer Port 1 (LPT Port 1):

1.     Click on the plus next to the category "Ports (COM & LPT)"

2.     Right-Click on the entry "Printer Port 1 (COM)"


3.     Click on "disable"


4.     When the message "Disabling this device will cause it to stop functioning..." is displayed, click "Yes".


5.     The device will now be displayed with a red cross over it's icon. This indicates that it has been disabled.


6.     Repeat steps 1 to 4 for all the devices you are sure of that you are not using them.

7.     Restart your computer.

8.     After the computer is restarted, click on "Start"

9.  Click on "Run"

10.  Type "msinfo32"

11.  Click "OK"

12.  Click on "Hardware Resources"

13.  Double-click "IRQs"

14.  Check if the IRQ assignment has changed for the M-Audio Delta.

If the IRQ assignment has changed, you can now test if you still get Pops and Clicks when recording or playing back audio. If the IRQ assignment is still the same or you still get Pops and Clicks we recommend the following:

1.     Shut down your computer completely.

2.     Unplug the power cord.

3.     Open the computer and touch a blank spot on the chassis to discharge any possible static electricity (static electricity can damage electronic devices)

4.     Physically remove the M-Audio Delta.

5.     Re-Connect all computer cables and start the computer (without the M-Audio Delta installed)

6.     Shut down the computer.

7.     Unplug the power cord.

8.     Touch the computer's metal chassis to discharge any possible static electricity.

9.     Install the M-Audio Delta (make sure NOT to install it into the PCI slot next to the Video/ Graphics card - also it would be a good idea to install the card into another slot than the one you used before, since this would increase the chances on an IRQ re-assignment).

10.  Connect all wires.

11.  Start the computer.

12.  Re-Install the driver if necessary (only necessary if the "Found New Hardware Wizard" starts).

13.  Check "Start/run/msinfo32/Hardware resources/IRQs" to see if the IRQ assignment has changed.

Check if the IRQ assignment has changed and if you still get Pops and Clicks in the audio. If the problem is still there, you might have to move the M-Audio Delta yet to another PCI slot or will have to disable more devices in your computer that you are not using. Intermediately and after making changes, restart and check if you still get Pops and Clicks when recording or playing back.

In most cases, providing free resources by disabling unused devices in combination with moving the card to other PCI slots should resolve the problem. In some very, very rare cases, you might still be stuck with an IRQ conflict and it might take more extreme measures to get rid of this problem.

As you might recall, we were talking about Windows' ACPI mode versus its' "Standard PC" mode earlier in this document. As mentioned earlier, the ACPI mode (in which Windows 2000 and Windows XP install by default) is designed to manage the sharing of IRQs and is supposed to be able to share and assign IRQs in a manner where no problem will appear. If Windows fails to manage this job in ACPI mode, it might be necessary to switch the Computer to "Standard PC" mode in order to regain control over the IRQ assignment. There are some things you need to be aware of though:

-       Standard PC mode will not run on Dual- and Multi Processor Computers

-       Standard PC mode will not run on Laptops (when running Windowx XP or Windows 2000)

-       In some cases, switching to Standard PC mode might keep your computer from booting up and will make it necessary to re-install Windows completely. This means that there is a high risk to loose all Data on your harddrive. BACKUP YOUR DATA before you decide to switch to Standard PC mode!

-       ACPI mode can cause trouble on many mainboards that were not designed for this operation mode. This applies to most mainboards build before the year 2001. If you have an old mainboard, we actually recommend running Windows in Standard PC mode. The risk to lose data when switching from ACPI to Standard PC mode remains the same!

We do not take any responsibility for lost Data and will not assist you in recovering your computer if it does not boot up anymore after switching to Standard PC mode. This is a "Last Resort" solution that you will have to perform at your own risk! Try this only, if you know how to recover your Backups and know how to re-install Windows, since it might become necessary!

If you completely understand the risks, but still want to continue, here is how switching to Standard PC mode works:

Switching to Standard PC mode in Windows 2000:

1.     Go to the "Device Manager" (see earlier - start/settings/control panel/system/hardware/device manager)

2.     Click on the plus next to the category "Computer"


3.     Double-click on the entry underneath "Computer" (similar to "Advanced Configuration and Power Interface (ACPI)"


4.     Click on the "Driver" tab


5.     Click on "Update Driver"


6.     Click "Next" when the "Welcome to the Upgrade Device Driver Wizard" screen is displayed.


7.     Select "Display a list of known drivers for this device..."


8.     Click "Next"

9.     Put the Radio Button next to "Show all hardware of this device class"


10.  In the field "Models", select "Standard PC"


11.  Click "Next"

12.  When Windows shows a message like "Installing this device driver is not recommended since Windows cannot verify that it is compatible with your hardware...", click "Yes".


13.  Click "Next" when the Wizard displays that "The Wizard is ready to install the driver for the following Hardware Device: Standard PC...".


14.  Once "Completing the Update Device Driver..." screen is displayed, click "Finish".


15.  Windows will inform you that you need to restart the computer for the changes to become active. Click "Yes" to restart the computer.


16.  After restarting, the computer will reinstall the drivers for every device installed in your computer. Most likely you will be asked to insert driver CDs for all the different devices that you've ever installed in your computer. Follow the instructions on screen.

Once all the drivers are re-installed, open the Device Manager and check if you see any Yellow or Red question marks or exclamation points. If so, this device hasn't been installed correctly yet. We highly recommend installing all devices so you don't have any warning signs (question marks or exclamation points) anymore before continuing to troubleshoot the M-Audio Delta.

With the computer now running in "Standard PC" mode, we have more options to assign IRQs to the different components of your computer. Although Windows still doesn't give us any options to assign IRQs, it will now accept IRQ reservations made in the computer's Bios (Windows will ignore these assignments when running in ACPI mode). Go to "Start / Run / msinfo32" again and make a note which IRQs are available (these are the one's that are not listed here). Restart the computer and access it's Bios (as explained earlier in this guide). The Bios category you are looking for is called something similar to "PCI configuration" - the exact name will depend on the individual Bios make and model. In here, you will be given the option to assign IRQs to the various PCI slots. The PCI slots are numbered starting from number 1. Number 1 is usually the first white/beige slot, located next to the AGP-Slot (brown) in which your video card is residing - you start counting at this slot (don't put the M-Audio Delta in this slot though, since it is always sharing IRQs with the Video Card). Figure out which slot you have the M-Audio Delta installed to. Then assign an available IRQ to this slot from the Bios. Save the changes in the Bios (F10) and restart.

After restarting your computer, check "Start/run/msinfo32/hardware resources/IRQs". Windows should then accept the assigned IRQ for the M-Audio Delta. The M-Audio Delta should now have its own IRQ which will ensure that it doesn't have any conflicts with other devices.

Recording- or playing back audio should now work without any interference like pops or clicks.

If you still get pops and clicks, please have a look at the beginning of this document, where we have listed other possible causes for pops and clicks.

After you've tried all this but are still experiencing pops & clicks in the audio, call our Tech Support team for additional assistance or help on the determination and solution of the problem.