Analyzing the
audio could certainly be useful - that is exactly what the problem is! Something nasty ending up in the audio - so looking at it in the frequency domain may provide some very helpful clues. If there is any periodicity to the noise then that information may just lead us to the source.
I have a bunch of very nice analysis tools available (my main work is flight simulator audio) and would be happy to see what I can find.
- GY
