PDA

View Full Version : Audio issues on early 2012 build MBP



MichaelH
11th December 2013, 05:39 PM
A few weeks ago, I won on eBay a late 2011 (Feb 2012 build) MBP, which came installed with Lion 10.7.5 (I upgraded from a late '09 Mini with Snow Leopard). It's been good so far and the specs are plenty for me 2.8GHz i7, 4MB RAM. I ran Tech Tool Pro tests on it and all fine.

Except... the sound quality has been better than I expected, until a couple of days ago when it started breaking up and distorting at random intervals, whether I play via iTunes, Toast Titanium, Audivarna etc. I mainly use the computer for sound-relateds tasks so this is disconcerting. Am I right in thinking this might be a Lion related issue than anything else?? It seems to have a bit of a reputation... I'm listening via good quality headphones, which are plugged in fully. The issue sounds like what you'd get if one was jiggling a loose headphone jack while music was playing, except the jack is fine.

Last night, the sound was breaking up at random. It's not the files themselves as on replay, those bits sound fine again. Today, on awaking the MBP there was no sound at all. Also under Sound in System preferences, the Output / Headphones started saying "The selected device has no output controls". I restarted and reset NVRAM. It was better for a while but somewhere through playing some files, it all came back including the "no output controls". Is this something an update to Mavericks might fix? Or is there something else I haven't tried?

I lost sound again later. Restarting coreaudiod through the activity monitor brought the sound back but didn't fix the breaking up / distorting sound. Interesting that at the same time as all this, playing the file waveform via an audio editor (Sound Studio) works with no issues. Input is also fine, as I just recorded a little something. Also, the balance settings for the headphones miraculously re-appeared while I was doing the above. Colour me confused... Any help appreciated!

bennyling
11th December 2013, 06:47 PM
Try a fresh/other installation of OS X. If that doesn't fix the issue, then it's a hardware problem.

MichaelH
11th December 2013, 09:34 PM
Yeah, I only have an installation disc for Snow Leopard though, which would be going backwards. Because I have a low monthly GB amount (3G), downloading Mavericks isn't really a viable option either. If there's a way of doing so at an Apple store, I guess I could try it that way but was hoping there might be other options to try... cheers

bennyling
12th December 2013, 05:40 AM
If you can install Snow Leopard onto a USB stick then that would also work.