2011 13" MBA Headphone Buzzing

Question

Level 1

0 points

2011 13" MBA Headphone Buzzing

Hi All. Under the following conditions:

2011 13" MBA with Lion 10.7.1
Sennheiser PXC 450 noise-cancelling headphones (in normal mode with NoiseGuard activated, i.e. noise-cancelling turned on). (I have some Buy Other Sound Equipment QC15 'phones as well, but not with me currently and can't test)
MBA charger plugged in
not playing any sound on the MBA and not touching it (not grounding it with my person)

I'm finding that there's a good amount of buzzing/white noise. It clearly seems like a ground issue because the buzzing stops if I do any of the following:

I touch (and thus ground) the MBA
I put the headphones into bypass mode (so they act as "regular" headphones); presumably any other "regular" headphones wouldn't exhibit buzzing either
Unplug the MBA from the charger

I'm not convinced the grounding issue is in the wall outlet because I've tried a few outlets already as well as plauuging the charger into a UPS / power conditioner. Again, passive headphones don't seem to have this problem; only these active Sennheiser noice-cancelling headphones so far exhibit the noise (my other NC headphones are at home and will have to try them later).

Anyone else with a similar setup that can confirm or deny this behavior?

Thanks,

Keith

MacBook Air, Mac OS X (10.7.1)

Posted on Sep 27, 2011 1:14 PM