Buzzing during audio playback

[Cary_Clark]

I am working on a G5 1.8GHz PPC Mac with Protools LE 7.3.1. My system preferances are configured to have my Mbox 2 manage all of my computer audio. I have noticed that when the computer is on and not running applications with sound content my speaker system is silent. When I launch or use any applications that play back audio (such as protools or itunes) my speakers begin to buzz while playing or standing by. When I exit the program the buzzing stops. Has anyone else had this problem and how can it be fixed?

[Phil Ogden]

Deleting Prefs and DDB's is always worth a shot with random problems like these. Failing that, it maybe some kind of RF interference. Do the cables to your monitors pass near anything that might cause interference (e.g VGA monitors).

Also, there's a bit on Answerbase about Mbox interference issues (reproduced below),

Mbox or Mbox 2 experiences whine or high pitched noise while in use.
The problem is related to either the computer itself, or to ground loops induced by plugging gear into multiple outlets or just plain bad grounding. The Mbox is generally not the culprit.

The following steps can help resolve the issue:

1) Plug all gear into the same outlet and/or make sure your outlets have a good ground.
2) Use TRS (balanced) cables from the outputs of the Mbox.
3) Get a Monster 'Ultimate Performance' USB Cable

If you are on a G5 and the above recommendations don't help, you can install the Apple Developer Tool called CHUD which helps remove noise cause by the processor to be eliminated.

More information on installing CHUD: http://www.digidesign.com/index.cfm?...1&itemid=20534

Further troubleshooting and help with 60 cycle hum issues

http://www.myspace.com/philogg

[NickRParsons]

Did you ever find an answer for this?

My g5 is doing the same thing. I've bought amazing cables, and tried the xtools and chud installation. the CHUD installation won't do what it says it will do - there's no processor option in the system prefs, I tried uninstalling it and now I can't even reinstall - seriously annoying.

Any results or ideas from anyone else?

Running 10.5.6 and PT 7.4.2 LE. Thanks!