Originally Posted by whiteknuckles
...I am thinking that when the volume is too high, perhaps the microphone is picking up the output of the headphone, creating a small amount of feedback. Any thoughts on this?
I don't think that is it.
I've experienced the sound since my QC1 and still get it on the QC2 when connected to IFE. If I use the low setting on the QC and turn up the volume on the source, then the sound is drowned out. It's very loud when using the high setting.
I don't get this sound from any other source such as my laptop or iPod. That leads me to believe it's coming from the IFE system.