MacBook Air constant high pitch sound from audio jack

Hi there,

Just wanted to let you know I spoke to someone at the 800-number today and they sent me to a KB article: http://support.apple.com/kb/HT2743?viewlocale=en_US

Following its advice, I purchased a ground loop isolator from Radio Shack: http://www.radioshack.com/product/index.jsp?productId=2062214&tab=summary

and the noise is gone! Note that the noise never occurred when using the same setup with my Unibody MBP or MB, only with my MBA.

Good Luck!

Hi Christian,

What if you try connecting some headphones into the port? Does everything work normally or are you getting the high pitched sound there as well? What sort of audio cable are you using? It's plugged directly into the TV or some sort of speaker system?

I'd say if no matter what you plug into the audio jack, there's a high pitched sound coming out then it's more than likely an issue with the port and you'll have to pursue service of the unit. If the noise is specific to that cable or the TV configuration, then it'd seem less likely a computer issue and potentially a TV and/or audio cable issue.

Hi there,

I have the exact same problem... I have a MBA (June 2009) SSD which experiences a high pitched noise out of my audio port. I connect a mini video port to a dvi-hdmi cable adapter. I previously used this same setup on my MBP. So, I answered your questions. I'm pretty sure I need to service the unit.

What if you try connecting some headphones into the port? Does everything work normally or are you getting the high pitched sound there as well?

Yes, same noise. Harder to hear cause the MBA amplifier *****, but its there. My Shure heapdhones don't lie.

What sort of audio cable are you using?

1/8 Stereo to RCA, with a recessed iphone (1g) adapter. Also tried the adapter from my headphones.

It's plugged directly into the TV or some sort of speaker system?

Into my speakers, but same when I tried the TV

Hi sum1else,

Given that you can replicate the issue across multiple input/output devices, I think you're spot on in saying that the next step is to arrange carry-in service to an Authorized Service Provider or Apple Retail Store (Genius Bar). I'm sure in their triage they'll be able to determine a fix/solution for you.

I have the same problem. This only occurs when I have both audio and video in use simultaneously. I'll try the ground loop isolator. I had been under the impression that this would only occur if I had the computer and my stereo receiver running on AC and plugged into different outlets. The high pitched sound occurs whether on battery or AC, and if on AC when plugged into the same power bar...

Would you guys say that assuming the ground loop isolator works, there is a design problem with the MBA? Again, I am experiencing this problem both when running the MBA from battery and from AC outlet. Or, could there simply be a problem with my specific MBA? Thx!

Same problem here. To me it seems like a design problem with the MBA. It does not happen with any of my other computers. Perhaps it is specific to the MDP though. Given it is is a physical issue with feedback and ground loops, probably not anything that can be done about it within the computer.

could it be the microphone feeding back because of the TV speakers? Try muting your microphone in the sound preference panel and see if it goes away.

I have the exact same problem. It's definitely a MBA design issue.