[LAU] Issues with JACK

Hello! I'm experiencing some weird issues with JACK. I got a new system the other day, and I'm tweaking it for linux audio only basically. My issues are: even when dsp load isn't even close to 100%, I get xruns. This only happens at lower latencies, but still. My setup is as follows : Kxstudio 12.04.2 3.2 realtime kernel (tried lowlatency and generic aswell) Usb sound card Lexicon Omega Realtimeconfig quickscan shows everything green except cpu governors, but I'm pretty sure I don't have that on this system? It's an Intel i5 3570k desktop. Or maybe there's some setting in BIOS equivalent of cpu governors? If so that might very well be the problem. I use JACK at 48khz 3 periods/buffer. I start it via falktx's Cadence. Any ideas about this? Also! When I'm asking for help anyway... I connect my MIDI keyboard via MIDI in on my sound card, but that suddenly stopped working. The midi out from the sound card is present in JACK, but it delivers no midi. Any idea on where to start troubleshooting this? Thank you so much for taking the time to read this. Cheers!