Quicktime on Mavericks outputs stuttering audio.

NIGHTMARE! I spend 3 hours trying to figure out why my typical workflow was not working. I am taking HD video and converting to 480p for the web. I've done this hundreds of time. Quicktime/Mavericks produced stuttering video, the uploaded video just churned online, and was essentially unusable. Strangely, it would play out of dropbox. Fortunately, I'm still running QT 10.1 and Lion on my old computer and could convert my video. Btw, the same setting on QT 10.3 produced a file size of 72 mb, on QT 10.1 58 mb.

I looked into QT Pro and the reviews are atrocious. Why bother?

Anyone have a good solution for reducing file size?

Kim, if you have a professional editing software, try reducing the size through it. In my case, files having trouble in QT stilll work in software like premiere. MPEG streamclip would traditionally be another option, but I am not sure how it works now in Mavericks, since Apple has made it more and more difficult to use this program.

Meanwhile, I would advise to keep making bug reports at http://www.apple.com/feedback/macosx.html

I am still hoping for Apple to fix these issues, or else I will have to reformat our computers and go back to Mountain Lion.

Thanks, Miguel. I do have professional editing software and have a solution. I alway produce a high res and easiest solution for years was to just export as 480 in QT. Since I was on a new computer, new OS, new QT, new version of Premiere, it took awhile to isolate the issue. Given that the export to 480 seemed the simpliest of all the above, it was the LAST thing I looked at!

I used Adobe Media Encoder and it worked like a dream. QT is now just for playback.

Great! I use the Adobe suite as well and it helps a lot. However, Apple should urgently fix these issues. We have simply lost the possibility to preview files -either as thumbnails or by hitting the space bar. It reminds me now of PC! Not to mention that QT won't play the files either without first converting them.

I too am experiencing stuttering audio in Quicktime on OS X Mavericks when the primary audio device is set to my Focusrite Saffire Pro 14 fireware audio interface. If I set the audio device to the internal iMac audio device, it does not happen. Audio works fine in other applications using the Saffire, including iTunes and Logic Pro X. In fact, if I run Logic Pro X and play some audio through it, leave it open, then play audio through Quicktime, then Quicktime does not have the issue. For now, I actually went back to Mountain Lion until the issue is resolved.

I reported the bug to apple:

http://www.apple.com/feedback/macosx.html

And to Focusrite:

http://us.focusrite.com/answerbase/contact

One of the posts in this thread mentioned keeping an eye on the Saffire mix control beta releases. That appears to be here (but no beta release yet to fix this):

http://beta.focusrite.com/releases/saffire_mix_control/

Miguel, I preview the videos in Bridge.

yes, Adobe Bridge will also work, but still the whole thing is a big, big inconvenience

You'd think such a simple problem would be easy to resolve. Come on Apple! Make it happen!

This is ridiculous! My entire workflow is totally messed up now. Thought all my files had been corrupted, turns out it's the whole OS that's corrupted its own codecs! I would understand if Apple stopped supporting legacy files like .avi, but not being able to playback it's OWN video ecosystem?! That makes no sense!

I feel like it may be helpful to write again, although one post should really be enough.

@ Jacian:

EXACTLY. Dear Apple, give us a quick patch. It's not like some obscure graphics programme won't work with a Wacom board when Firefox and NeoOffice are on at the same time. - - - Apple Quicktime codecs won't play!

I'm annoyed by this, too, but why is everyone assuming this is Apple's fault and not focusrite's? Hopefully, the two companies can work together to resolve this problem that didn't show up in their testing.

I have the same symptoms with a presonus Firestudio Mobile.

So it's. It limited to focusrite. Problems stop if I use built in audio.

That should read it's NOT limited to focusrite.

It's not limited to Focusrite. I have the same problem if I use Soundflower to route audio. Stuttering only happens in Quicktime, iTunes, system sound effects, and the native HTML player in Safari, but it's there and persistent.

The developers of Boom also had the same problem, but they've mostly fixed it in the latest update. But when I use Boom as the output device, the volume up/down sound is noticably laggy.

I also see the converting problem for Quicktime videos.

I’ve spent a lot of time getting my video collection just so, and now some fool idiot has messed it all up -- arbitrarily and without warning. This is extremely disturbing and whoever let this happen should be demoted and replaced by someone who will make it right.