Audio Playback is terrible, what can I do? (WindowServer 99.8% CPU!)

Question

Hey all, I've got a strange problem. I can't do smooth playback on videos. When I say "smooth" I mean I can't get more than a second of playback. The video normally remains stable, but the audio is awful. Choppy, I can hear clicks and pops, sometimes totally stalls. The only way to fix this I have found is to change the output device in System Preferences and then change it back.
A common theme I see when this happens is WindowServer pegs out one processor (99.8%!) and will remain that way until I stop playing the video.
I've repaired permissions, I've done all of the basic troubleshooting and I have no idea.
Looking in system.log I see this hundred of times:
Apr 3 00:54:42 computername kernel[0]: IOAudioStream[0x3af6100]::clipIfNecessary() - Error: already clipped to a position (0xa43,0x1829) past data to be clipped (0xa43, 0x59c) - data ignored.
WindowServer.log doesn't contain anything relevant, it only displays messages from SynergyServer (An application to redirect mouse and keyboard movement. These problems exist when I don't use Synergy)
Dual 2Ghz G5   Mac OS X (10.4.9)   3GB memory, Radeon9600Pro&Radeon9200; 3 Displays

Answer 1

Hi,
For what it's worth give the utility Audio MIDI Setup a try.
- Open the folder Applications, open the folder Utilities, open Audio-MIDI-Setup.
- Switch to Audio-Devices
- Look at all fields that say something like 44100.0 Hz (especially at Audio Output)
- If there is any other Hz value in these fields, switch it back to 44100.0.
- 44100.0 Hz is the normal sampling frequency for consumer computer audio. If there are different value in your Audio MIDI Setup app than either the digital to analog converter or your speakers will stall or sound distorted...
Cheers,
Walter