Pro tools HD9 crashing idling

[zenmasterwombles]

First post, but been reading for awhile you guys are awesome!

I have yet to find a fix to this, I have MacPro with dual 2.26Ghz quad core, 10.6.8 OS, I have had problems with it crashing while idling, while I set up my hardware (guitars, mic etc) I come back to the computer and it gives me pro tools crashed unexpectedly error. It has done this many times, while I havent done anything, just a master and audio track loaded up, one armed no inserts.

I checked my harddrive fixed all errors, its good to go now, thinking it was that. I think that it may be something with read/write maybe? or autosave? I have 3 harddrive inside. I have checked the ram its good, but its seems to be crashing not even when stressed (thinking it could be ram) Any ideas or links to other posts?

Thanks in advance!