[quote="-JK-":2zjtuou0]UPDATE:
I tried to edit the DSDT (thanks to john_neg for his help), but that didn't change anything, I still got DAE error -9162 and couldn't start Pro Tools HD. Then I switched the mainboard to an ASUS P8B-C/4L, and suddenly Pro Tools booted without errors! But, and that's a big BUT, playback doesn't work as it should.
The sound is looping and there's heavy distortion on Mac OS. On Windows everything's running fine and smooth, even smoother as I imagined it to be!
So it seems I'm running out of options, and I'm seriously considering buying a Magma chassis and a Mac Pro right now. So if anyone is interested in my Supermicro X9SCA-F or my ASUS P8B-C4L just send me a message.
Regards, JK