Creative Cloud Premiere CS6 - no playback at all

Hello there,

I can place clips and audio onto the timeline and scrub through the frames seeing them but nothing plays.

I can't playback audio or video (tried many codecs) in the source window, timeline or from the imported clips.

Hitting the space bar or appropriate playback button yields no results.

My colleague has the exact same imac late 2012 and it works just fine.

I tried reinstall but it didn't make a difference.

This is so annoying. Please help