My first thought would be that the person has some bad RAM. It's also possible that the firewire connected device has gone bad. It also couldn't hurt to check the website of the maker of the device and software to see if there are any known issues with 10.6.6. A lot of times "specialty" apps tend to be horribly written and are incredibly fragile so that seemingly simple changes will cause them to break. Since there's little to no competition in their particular niche, and they tend to have you because of the amount of money you've already sunk into their product, there's little to no incentive to really improve the software in any substantial way.
I'm trying to help someone whose English is not good.
He has an Intel Mac running Snow Leopard OSX 10.6.6 (according to the crash report), although uname -a gives
Darwin-ordinateur-de-apple.local 10.6.0 Darwin Kernel Version 10.6.0: Wed Nov 10 18:13:17 PST 2010; root:xnu-1504.9.26~3/RELEASE_I386 i386
He uses LogicPro 9, and DigiCoreAudio v. 8.0.3
Connected via firewire is a Digi 002 running ProTools.
All ran as merry as a marriage bell like this until the upgrade to Snow Leopard, which he did using the 29 euro upgrade, not the "box set".
He now has random crashes - the system will run for a while, then crash.
He has sent me a PDF of a crash report which I don't know how to attach on this forum; it gives:
Exception Type: EXC_BAD_ACCESS (SIGBUS)
Exception Codes: KERN_PROTECTION_FAILURE at 0x0000000000000000
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
From what follows this, it seems that DigiCore Audio Manager starts four times just before things grind to a halt.
Is anyone else using this setup? Any ideas?