Pops and clicks on heavy sessions

[stevesound]

I'm getting this annoying problem -

when I run a reasonably big session (20-40 tracks, maybe 30-50 plugins) I get intermitant pops and clicks, even when the session isn't playing. It's kinda like the sound you get if you try to record thru the adat without making it the master. I've mixed stuff down and the pops and clicks don't turn up on the mixdowns, so it's just the output on large sessions. Any ideas? I've been trashing prefs, etc to no avail....
I'm on 7.1 dv toolkit with a 2.7 dual g5 4.5G ram.

[JohnnyG]

Are you seeing the pops in the metering? Or just hearing it?
Try the CHUD tool for the Mac G5, it can help with noise, but it's usually for high pitched whine from G5's.
Is the noise in the headphones too?

[stevesound]

They're not metering, it's just coming out of the 002r speakers. I'll try that tool, thanks for the advice