A brief explanation of USB audio problems:

Most USB audio problems are caused by data transfer interrupts on the USB stream that is feeding audio from the driver to the soundcard. If the computer fails to meet the system specifications required, the result can be a white noise burst from the audio device. USB interrupts generally do not effect most USB devices such as printers, keyboards, mouse, etc. as these devices use a USB bulk mode of transfer and do not produce noticeable problems if data is interrupted.  There is not have a one size fits all resolution to ensure error-free performance of all audio devices on all computers, but most USB interrupts can be resolved by one or all of these actions:

1. Remove USB hubs from your system: Line 6 does not support the use of USB hubs for any Line 6 product.  USB hubs can also cause white noise or audio interrupts.  Please disconnect the hub and plug your cable directly into a USB port on the back of your computer if you are using a USB hub. Mac users: Make sure you are connecting directly to your computer and not your keyboard (as this acts essentially like a USB hub).

2. Adjust the buffer size in your preferences:

PC: Start > control panel> select classic view if you are in category mode > Line 6 Audio and MIDI devices

Mac: Apple > System Preferences > Other > Line 6 Audio and MIDI devices

The driver console will display a Buffer Size slider that you can adjust towards EXTRA SMALL, MEDIUM, or LARGE. Please first move this slider to MEDIUM or LARGE to see if this helps. Your objective is to have little or no latency while eliminating that white noise.

3. Disable wireless networking devices: On some CPU configurations, actively using wireless networking/connectivity while streaming (recording/playing)computer audio can impact the fidelity of the audio streams (e.g. noise or artifacts are heard in the audio while using wireless connectivity). Disable wireless connectivity while recording and playing audio-over-USB. A known issue for Mac OSX 10.4.11 users as of May 2008 was an update from Apple that causes audio glitching and stuttering effects during ANY audio playback with USB interfaces if Airport Wireless Networking is enabled. The solution is to disable the device during Audio runtime of USB related interface units.

4.Laptops: Change the Power Schemes on your computer (PC's only). To change the Power Schemes in Start/Control Panel/Power Options/ within the power options menu change power schemes to "Always On". Also, underneath the Power Schemes, please make sure that turn off hard disks, system hibernate and system standby are all set to "never".    

5. Purchase a PCI based USB card (desktops) or PCMCIA USB card (laptops): These cards often solve the problem of white noise because the USB implementation on these cards overrides the USB built into your computer. For more information on PCI Cards please visit

Chipset Error Explanation:  If the computer fails to meet standard USB requirements, a possible result the soundcard creates a "white noise burst" at the analog audio outputs. This is caused by a flaw in some USB chipsets that were manufactured by Intel using the ICH6 architecture. The chipsets we have verified as having this problem are the 915G, 915P and 925X chipsets, although others may be affected as well. Intel publishes on their web site an Errata that provides a more detailed explanation. Please note that computers that create this problem produce problems with all USB 1.1 audio interfaces, not just those manufactured by Line 6. For instance, Digidesign provides their customers with similar information on this Intel chipset problem. Also note that your computer may have this problem even if other USB devices seem to behave normally. This is because other USB devices (like USB printers and hard drives) generally use USB's bulk mode of transfer, and do not produce noticeable problems if data is momentarily interrupted, as on these problem Intel chipsets. USB 1.1 audio devices, which have to continually input and output audio data at a fixed sample rate to provide audio, require USB's isochronous transfer mode, which is intended to guarantee the steady flow of data that is required for audio. These Intel chipsets fail to consistently provide the continuous data flow required for the isochronous mode and audio. If you want to know if your chipset is one of the affected ones, go to

and download the program CPU-Z 1.30. This program will gather detailed info on your CPU. Once downloaded, run the program, select the "Mainboard" tab and note the information where it says "Chipset" (e.g. Intel i915PM/GM/GMS Rev 03).

Solution: We do not have a solution that ensures proper performance on these computers. The most successful workaround we have found is adding a PCI based USB card (to desktop computers with these chipsets) or a CardBus or PCMCIA USB controller card (for laptops with these chipsets). Once these cards are installed, these computers often stop exhibiting the "white noise burst" problem, because the USB implementation on these cards overrides the flawed built-in USB implementation of the computers.

Note: ISA motherboards operate at lower bus speeds, and can slow down your computer and can sometimes cause "clicks" in the audio. We recommend using a non-ISA board.