UR 12 distortion when playing audio

I have the UR 12 and it seems every time Im playing audio it gets distorted after minutes of playing… Ive ofcourse unistalled and downloaded the latest firmware and even went back to an older version and it still exist. the problem is consistant and annoying… Im using macintosh 10.11.2… Again this happens even when im playing audio from itunes… I did check around and see this is a known issue, I just havent been able to solve… Any help would be appreciated, thanks!