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View Full Version : 2011 13" MBA Headphone Buzzing




f00f
Sep 27, 2011, 01:38 PM
Before I continue -- yes -- the solution is just to ****ing crank the volume! And listening to Anterior's latest offering (http://itunes.apple.com/us/album/echoes-of-the-fallen/id451599212) at the moment rest assured that is exactly what I am doing! lol Regardless, for the rare but necessary quiet times it'd be great if this MBA didn't buzz through the 'phones.


2011 13" MBA with Lion 10.7.1
Sennheiser PXC 450 (http://www.sennheiserusa.com/noise-cancelling-headphones-stereo-500643) 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


With the MBA charging and the headphones turned on but no sound playing -- and when not touching anything on the MBA -- there's a good amount of buzzing. The buzzing ceases 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
Crank the tunes!!!! ;)


So it's some issue with the active nature of the headphone's noise-cancelling features, possibly combined with a bad ground of the headphones and/or MBA? I'd love to hear back from other 2011 MBA users with NC headphones.

Thanks,
f00f



f00f
Sep 27, 2011, 02:38 PM
To rule out the headphones I tried them in a 2010 21" iMac and a 2011 MBP (that was charging) with no discernible buzz. Have to try those QC15s later but have a feeling the Air will be to blame.

Simon86
Sep 27, 2011, 03:00 PM
I have a set of Sennheiser NC BT headphones (MM-550), and I should receive my new MBA in 7 days time. I'll try and test this issue, and report back :)

f00f
Sep 27, 2011, 03:22 PM
I have a set of Sennheiser NC BT headphones (MM-550), and I should receive my new MBA in 7 days time. I'll try and test this issue, and report back :)

OK that'd be great, thanks! :)

Right now it seems like a fault ground, just a question of where, and I can't get a better idea till I'm not at work.

f00f
Sep 27, 2011, 03:57 PM
Problem solved.

While I knew with near 100% certainty it was a grounding problem, I never thought to question whether my MBA's MagSafe was indeed grounded.

Well, unless it's used with the 3-pronged extension, it isn't grounded properly -- and I had been using it without said extension (it's at home). I just borrowed my co-worker's MagSafe extension & the buzz problem is gone.

Thanks to "Mario" at the Apple discussion forums (https://discussions.apple.com/thread/3349928) for this insight.