after having installed OSX Mountain Lion my sound startet stuttering whenever there is rapid movement on my screen.
This includes e.g. window movement, scrolling through image loaded websites or video playback (flash player, quicktime).
A restart didn't help. I'm using stereo output, not digital.
I have connected a second monitor but the problem persists after disconnecting it. Movement on the second monitor also causes the sound to stutter.
My GPU Diode temperature is at 85°C (there is some bug that keeps the GPU under load while a second monitor is connected AFAIK), but I guess it was the same under Snow Leopard.
In Snow Leopard the sound output was always perfect even under heavy load or heavy HDD I/O.
I, too, am having this sound stuttering problem...and it all started after I upgraded to 10.8. :-( I have a 27" 3.1 GHz Intel Core i5 with 16GB of memory. (My husband has an older 2009 model of the 27" and he is having the sound stuttering problem since ML too). I can promise you that we had no such problems before upgrading, and are not ones to constantly install new software/games/etc. We do both play World of Warcraft but have done so for a few years on our various Macs. We don't listen to music or watch videos much on our desktops, so I cannot speak to other sound problems, but when playing WoW and using Ventrilo, there are occasional stuttering instances. It is not very consistent (that is, always does it during X or Z). In fact, using Ventrilo tonight and had no problems, but a week ago experienced stuttering when someone else was talking.
I do wish Apple would AT LEAST release a statement acknowledging this issue. We both work in IT development, so we understand that there are sometimes mystery problems that take time to troubleshoot. NOT saying anything, however, just makes the company seem uncaring of its customers. Personally, I would be a bit more content if I KNEW that Apple KNEW and that they were looking into it.
While not an ideal situation, it's good to know we are not alone in this...
Your problems will most likely be related to OS X "sandboxing" just about anything you do.... Sandboxing was supposed to be a "coherent" feature. But wound up being a total performance killa... Apple have been working on this issue a LONG time since 10.8.2.... hence them releasing more betas of 10.8.3 than (I think) any other beta OS X before that... A HUGE problem causing havoc with almost ALL 3rd pty. high performance software..
If you are a CRACK... You can google-search (goes beyond this here thread) ways of "overwriting" what OS X regards as "Items/processes which should be sandboxd"... To STOP this non sense...
We had to manually delete A LOT of files on the OS to get our system running to accommodate a pro-environment. Even "Files" that Apple forgot to delete themselves.......(Do the G-search or this thread WILL be deleted... hence me NOT going into details)
What COULD help you is to safe-boot ONCE and log in.. Then boot normally.. That in MANY cases will take of the problems (short-sighted-ly)... Each time you re-experience the issue... Redo aboe