posted on Oct, 6 2006 @ 04:55 PM
Listened to the mp3, I don't know what this is, sounds a bit like an electric motor or hard drive writing.
It's common for some digital camcorders with onboard mic to produce noisy recording problem, an external mic must be plugged for better audio
quality.
If this was only momentally noise appearing for a short time on your recordings, then this could be any electromagnetic interference as ThePieMaN
mentionned.
For example I hear this kind of noise often with my radio scanner tuned to certain frequencies near my computer, I can hear a slight screeching noise
matching exactly the cursor movements on my screen, or on some other freqs I hear similar noise corresponding to the processor busy on ressource
intensive tasks.