Thanks for the additional info...you never know when it may come in handy...especially if certain models had well known specific issues.

Wow...it really sounds like from your original post that you have done quite a bit of troubleshooting on your own.

First let me ask if you happen to have any Applecare warranty remaining on this computer (just as a "safety net")?

Some things to consider:

- What version of the Mac OS are you running?
- What version of Logic are you running?
- Do the problems you're experiencing occur only within specific software applications...or could you restart your computer (not open any applications), and have the problem(s) occur?
- Any chance your hard drive could be going bad?
- Have you had any recent thunderstorms or home electrical issues that could have damaged something in your computer?
- Did you install any new hardware or software recently...and then the problems started?
- Have you tried booting your computer from a Mac OS DVD (or your hardware test DVD) to see if the problem occurs? I don't mean run the hardware test (I know you already did that)...just booting from something other than your internal hard drive to see if the problem still occurs.

Just a bunch of stuff to consider on top of what you already tried.

Hope this helps,

- Nick

p.s. I know that you said that the nearest Apple Store is an hour+ away. But if all else fails, this may be your last option...instead of "banging your head against the wall" trying to figure it out. Since the folks at the Apple Store have additional specialized hardware equipment & software applications to test your computer more throughly.