There have been reports of sound distortion/pollution on the APAD sound channels.
Here is a visual representation of the noise:
We see that after the initial configuration of the power supplies(at about 25 seconds), the right channel( lower image ) line thickens after about 45 seconds (just prior to the 00:01:00 minute marker), indicating a tripling of background interference.
Please refere to the following link: A8 sound fix