Soundblaster X-Fi Crackling and Popping Update

Scenario 1

A game's audio samples have levels or DC biases that are unusually high. These samples have been found to overload the X-Fi audio enhancement algorithms which result in output streams that clip, or exceed the allowable output signal swing.

Solution: Reduce the game's audio level. Where this is not possible, reduce the master volume level in Windows.

Scenario 2

Very lengthy handling of Interrupt Service Routines (ISR) and Deferred Procedure Calls (DPC) by the graphics driver on nForce motherboards (Asus, MSI, Gigabyte are some motherboard vendors that use this chipset) particularly when nVIDIA SLI graphics are used. One game where this problem has been observed is the game Farcry, but other games may be affected as well. These times have been observed to be as long as 100 milliseconds and causes the audio data buffers handed to the sound card driver by the application to become stale.

Possible Solution: A third party tool called "nHancer" (www.nhancer.com) has been found to make it possible to mitigate this problem by retuning the graphics driver. We recommend setting the AFR (Alternate Frame Rendering) mode in nHancer to reduce the maximum interrupt deferral times (called DPC) to the 10-25 millisecond range. This problem is not unique to X-Fi, it causes crackling/distortion with a number of other audio products we have tested.

Scenario 3

In a small number of cases the game crackling issues were found to be caused by the X-Fi driver related implementation.

Possible Solution: Download and install the latest driver from the Creative website here. As of this date it is a beta version (2.09.0001). This has been shown to resolve the crackling issues in this small number of user’s systems.

Scenario 4

X-Fi's requests for PCI bus service are being "retried," or deferred, an extraordinary number of times, presumably while the graphics system is using system memory when playing Battlefield 2 during complex graphics scenes. It may also occur in other games and is associated most often with nVIDIA nForce chipsets with SLI graphics. The SoundBlaster X-Fi sound card can withstand up to about 450 bus retries on occasion, but in these cases we are sometimes seeing over 8000 bus retries for a single request, for a total deferral time of up to 2 milliseconds (240 nanoseconds per retry). We have seen these deferrals cause audio defects in non-Creative PCI sound cards as well.

Possible Solutions:
- Use 2G of dual-channel memory
- Flash the BIOS or change CMOS can cause the memory and PCI performance to improve. Unfortunately in some of our tests this caused the performance to sometimes degrade. We cannot advise which particular BIOS versions improve performance and which reduce performance, but flashing the BIOS can cause the system memory resource allocation to change and updates are almost always reversible.
- Ensure that the SATA hard drive is not conflicting with PCI memory resources. Changing to a different controller may help.
- Sometimes removing one SLI graphics card, rebooting with X-Fi, then shutting down and reinstalling the second graphics card fixes the problem.

Scenario 5

Overclocking of nVidia based graphics cards has been found to cause crackling issues in Battlefield 2 and other gaming titles. Our internal testing has found that it is the card’s Memory Clock Speed that most directly affects the intensity and frequency of the crackling in Battlefield 2.

Possible Solution: Installing the nTune application from nVidia’s website will give you individual controls for memory clock speed and GPU clock speed. The slower the Memory Clock Speed, the fewer and more subtle the crackles. When turning the Memory Clock Speed down as far as the application would let us, the crackling disappeared entirely. We recommend that you reduce any overclocking and if necessary underclock your graphics card no more than necessary to resolve any audio crackling issue.

Follow these steps to modify the clock settings on your nVidia Geforce SLI graphics card/s (For other brands of graphics cards please consult the documentation for that card or contact the manufacturer):

1. Right click the Desktop.
2. From the context menu, choose Properties. The Display Properties window appears.
3. Click the Settings tab.
4. Click the Advanced button.
5. In the new window, click the nVidia tab (the one with the nVidia logo).
6. In the list that appears, click Clock Frequency Settings.
7. Select the Manual radio button.
8. In the Settings drop-down menu, choose “Performance (3D).”
9. Adjust the Memory Clock Speed to your specifications.
10. Click Test Changes.
11. Click Apply.

IMPORTANT: Changing the default clock speed on a graphics card can have unexpected results. Please consult your graphics card documentation for further details.

Conclusion

In summary we would like to highlight that based on our extensive tests our findings have shown that this issue is not limited to Sound Blaster X-Fi, in fact virtually any add-in audio card (and some MB audio based solutions) can exhibit these issues to varying degrees. Based on this and discussions with Nvidia, we therefore believe that this issue can only be completely resolved with a BIOS update from nVidia or the MB provider and our efforts to resolve this with them continue. In the meantime our efforts to alleviate the issues and find other workarounds also continue. We are additionally working on collating the full list of systems tested, which numbers over 50 different systems, and hope to publish this shortly.

On a final note, thanks to the feedback we have received through our forums, we have become aware of our users’ willingness to use beta release drivers. This is a very useful way for Creative to release updates and fixes earlier than we would otherwise be able to. Based on this we have initiated a full beta release program and will be issuing updates on a more regular basis than previously possible. To view a list of our latest releases, please click here.

For more information on this issue and any of the possible resolutions, please approach our Customer Support team.