M-Audio Delta 66 User Manual page 44

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 set in the Delta Control
Panel software. "+4" can handle much hotter signals than "Consumer" or "-10." If
you find that you are still clipping at the +4 setting, you will need to turn down the
audio at the source.
Possible Cause 2: If you are recording from the S/PDIF input, but you have
the Delta 66's master clock set to something other than the S/PDIF input, you are
recording an out-of-sync S/PDIF stream. This can result in lost or bogus samples
being recorded.
Possible Cause 3: 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 card calibration (sometimes called "profiling") the first time you use the software
with a new audio card.
Possible Cause 4: Some accelerated graphics cards use excessive amounts
of system bandwidth, preventing the recording buffer of an audio card 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: I'm getting some pops and clicks in my monitoring signal, even when
my system is idle.
Possible Cause: If the S/PDIF input is not muted in the monitor mixer, and
you have the Delta 66's master clock set to something other than the S/PDIF input,
you are monitoring an out-of-sync S/PDIF stream. This can result in lost or bogus
samples being monitored and recorded.
Problem: The sound from the monitor mixer is muffled. It sounds as if it were
running through a mixer with the treble control turned all the way down!
Possible Cause: The current Delta 66 sample rate is too low. The monitor
mixer is a digital device that runs at the current sample rate of the Delta 66 board.
The frequency response of the mixer is roughly one-half of the sample rate. There
is no way to prevent this lost frequency response while playing back or recording at
a low sample rate. However, it may be prevented when the system is idle. See the
"CODEC SAMPLE RATE" paragraph of the section 'Hardware Settings Page' for
more information.
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