Logic Pro 8 crashes after "Please select an audio driver in the following preference dialog". I trashed the two preference files in ~/Library/Preference but the issue is still happening. I tried reinstalling it couple times but the problem is still occurring.

I'd guess its either your version of Logic 8 or your soundcard ?
any details on either?

I updated it to 8.0.3 and I have Audigy 2 ZS as a sound card. I tried connecting an external sound card, which is 100% compatible with Mac and still crashing.

Which distro are you using? Do you have SSE3?

Just an advice...I would go vanilla for audio apps...in fact for everything. Many distros are not 100% correct, and may cause that kind of weird behaviours.

Yeah I am using XNU kernel with iDeneb 10.5.5. Problem is that the setup I have does not work with any other kernel. In fact it would not even boot into OS with anything else than XNU.

Oh and I don't have SSE3 on that rig. Only SSE2.

That's they key to your issue

So is it absolutely necessary to have SSE3 enabled CPU?

Yep. SSE3 emulation uses to give high cpu usage, and weird crashes. Os X uses sse3 binaries, so you really need a sse3 processor if you want a stable and fast system (belive me, you'll notice the difference)

Logic Pro 8 gets to initialise core audio and then crashes.
Anybody, help..