stuttering on every bar

[aegez]

im running 5.2 on a G5 with loads of ram... on every one of my projects, if there are multiple tracks running clips that are just looping, live stutters for a bit on every bar loop. it's ever-so-slight, just milliseconds, but is audible almost like a clip distortion or something.

i thought it was my hard-drive not being able to keep up, so i tried running the project off of a fast firewire drive. no dice.

then i tried putting all the clips into RAM, still no dice.

this happens durring parts in the song that may have only 6 or so tracks running, and none of them are overloaded with fx or compression etc. they all have 3-band eq's and not much else.

the sends a,b, and c each have a delay or reverb on them.

nothing crazy, i feel like this machine should be MORE than capable of running these simple projects.

of course, when i render to disk, it goes away, but in the monitoring stage its almost impossible to concentrate because of the click/stuttering.

any thoughts?

G5, OS x 10.4.3, 1.5 g ram, Live 5.2