M-AUDIO AP-012403 - Manual (Page 19)

Problem: Repetitious Sound.
Possible Cause: An IRQ resource conflict with the USB controller and
another device (PC only). Often this will result in a small segment of sound
(0.5 to 1 second) repeating itself over and over, sometimes completely
locking up the computer. See the general troubleshooting suggestions at
the beginning of this section.
• Problem: I’m getting some pops and clicks in my audio recording.
• Possible Cause 1: Input levels are too “hot,” causing clipping or input
distortion. Make sure you have the proper signal levels coming from your
source audio device, and lower the output if necessary.The incoming levels
may be easily viewed from the Audiophile USB Control Panel peak meters.
• Possible Cause 2: Your application software may not have the proper
audio buffer sizes set. Each software application handles this differently, but
typically there is somewhere in the software’s setup to set the size of the
playback and recording buffers used by the application. Some applications
also require you to run a calibration (sometimes called “profiling”) the first
time you use the software with a new audio interface. For instance, if the
clicks are present when using Cakewalk SONAR, then try to run SONAR's
Wave Profiler.
• Possible Cause 3: Some accelerated graphics cards use excessive
amounts of system bandwidth, preventing the recording buffer of an audio
interface from keeping up with demand. This can cause clicks in the
recording. Reducing or turning off the graphics card’s graphics acceleration
feature often resolves this problem. In Windows, the level of graphics
acceleration is accessed from Start | Settings | Control Panel | System |
Performance | Graphics.
Problem: My software application keeps telling me “sample rate not
supported” or some similar message.
Possible Cause: This would most likely occur if you were trying to select
96000Hz as a sample rate, and the Maximum Sample Rate available from
the Audiophile USB Control Panel is 48000. Open the control panel, and
uncheck the Active Port boxes until you have only one port selected for
either input or output.
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