Hi again, everyone.
I've had ML for almost 2 weeks like most of you. The video/sound stuttering, no sound at all, and paused video started immediately after I installed ML.
In this and other forums, I shared a long list of everything I tried. I sent this list to Apple also. Since then, I've tried at least a dozen other things (from ripping out files and external devices to installiing ML on a newly-formatted external HD to...well, the list goes on and on.)
However, I've now come to a new theory. I may be completely wrong, so I'm just throwing this out for opinions and discussion.
Whereas before I thought that the problem MUST be directly related to sound and/or to video, now I think it is a bigger, system-wide problem.
As others have discovered, since I installed ML, my mouse, menus, windows opening/closing, etc. sporadically will come to a halt. The mouse becomes jerky or completely unresponsive for 2-5 seconds, clicks on menus or buttons often do nothing for 2-5 seconds, dragging out windows can be unresponsive or jerky. This happens regularly with no other applications running.
Whether or not these system lags coincide with the video/sound lags is impossible for me to tell. It's the chicken and the egg problem.
However, my conclusion is that the video & sound problems we're experiencing are actually caused from an OS problem that is causing the mouse/menu/window jerkiness and overall slowdown.
Just a theory from one who has tried everything.
Opinions anyone? Best to you all. Hang in there, and let's hope 10.8.1 solves these issues!
I want to encourage everyone on this forum to email Apple, detailing every problem you've found with ML.
As Alleycat posted on July 28 in this forum:
No idea on a fix, but i think you should send some feedback to Apple here:
Apple should be sued on that, It was twenty bucks, but I don't pay twenty bucks to just have headaches!
I endorse the "NEW THEORY" by dcollett.seattle, I think this issue is more system wide.
I have a macbook pro 13" i7 early 2011 with 16GB of OWC RAM (also, because I thought my system was slow cuz of RAM).
Maybe for this system to work it out it needs to be upgraded to SSD too??
When I got Mountain Lion, the first thing I noticed was some slowness. Ok, after indexing, reboots, PRAM resets, disk permissions, etc... It is runnable, but
I STILL CAN'T PLAY MUSIC ON ITUNES!!!!
STUTTERS STUTTERS STUTTERS!!
I FEEL LIKE I WAS DOING COOPER WITH A DISCMAN.
I STILL CAN'T PLAY BIG VIDEO FILES!!!!
STUTTERS STUTTERS STUTTERS!!
And, last but not least, overall lag here and there still exists.
There's something wrong with this Mountain Lion!
Let's add this gamer reports to the "NEW THEORY":
"Since upgradingn to Mountain lion, I have seen my cursor jump around the screen randomly at times, and the audio will start to flake out randomly. I'm not sure if this is an incompatibility with Diablo three or simply a matter of mountain lion being unoptimized and again another one of Apple's disastrous software releases.
My hardware is a 2011 iMac with a 3.4 GHz I 7 processor, solid-state hard drive, 2 GB AMD 6970 video card, and 16 gigs of RAM.
Anyone else having this. Also, the stutter under ML seems to be more frequent and more rubber banding. Not sure if that is the OS or Diablos fault."
"I am having the same issues with Diablo III after upgrading to OS X 10.8 Mountain Lion: audio dropouts and cursor jumping.
I came onto the forums to see if it was only me.
I have the same hardware as Barrett as well, a fairly top-of-the line i7 iMac, 16 GB with an SSD drive.
Most of the time things work OK, but its fairly annoying. My wife's system next to me that hasn't been upgraded yet is not affected."
Suprisingly often, a top of the line 2011 iMac is mentioned. I do have the same issue with my i7 iMac and it often seems to be related to fullscreen video which leads to sound stuttering, but also background process and CPU usage seems to trigger it. In total, it's not very predictable though.
Pausing the audio or video sometimes helps, as well as leaving fullscreen temporarily, but usually it starts happening again after a few seconds.
It all began with the update to 10.8, so might also be a driver / firmware problem that's more specific to our hardware and Mountain Lion. Hope there'll be a fix released very soon.
I have had almost the same problems, although reading through the posts it seems to vary a lot. My cursor doesn't jump around randomly, and I can play music in iTunes, but I am having a lot of trouble with streaming video (I'm not sure about videos I have on my hard drive, but I think they're playing fine). The video problem is the same as OP: after some amount of time playing a video on, say, Netflix, the video and audio get choppy, and then get so bad I have to stop and restart. When this happens, though, the whole system is sluggish; my cursor is choppy, maximizing and minimizing are really slow, and it's slow opening programs. Restarting helps initially, although I've noticed my boot time is much slower than it used to be.
I've got the same issue described here but with a slight diference.
I have updated my macbook pro mid 2010 from lion to mountain and had no issues at all.
Then I bought an ssd and made clean install, now I have this stupid issue.. I really doubt that this is an ssd problem. But the truth is that if I switch HD's I have no video/audio problems with the old one.
Same issues here with Mac OS X 10.8, Mountain Lion. Sound stutters and breaks up, mouse curser lags and jumps around the screen, especially prevelent when playing World of Warcraft which makes it unplayable.
System specs are latest iMac, i7, 3.4 GHz, 16MB RAM. Hope there is a fix soon or wiping drive and going back to 10.7/Lion and forgetting about iCloud intergration.
I am getting really tired of this problem, my machine should be flying, instead it can't even handle a 1/2 hour podcast without breaking up! I've even tried letting it go to see if the sound will get better, sometimes it does, sometimes it fades to clicks and pops!
Apple had better get their fix in soon, everybody here has a newer machine and we are all experiencing this problem.
I think this weekend I'll put my Liion clone back on my iMac! Yesterday I had to use my Cloned Lion drive as the target disk just so I could watch a 1 hour TV show. Using a USB remote disk really slows the system down, but it played the show without any problems!
I'm debating putting in more feedback until this problem is fixed
PLEASE leave detailed feedback to Apple about this problem!
The more people who leave "official" feedback, the more likely it is that they will address this in the upcoming 10.8.1 patch!
This board is great to vent (which I've done several times here because I'm also very upset with the problem), but you need to keep writing feedback directly to Apple:
Let's cross our fingers that 10.8.1 solves this for all of us!