UR22 high-pitch noise during playback

I’m encountering intermittent, high-pitched noise during playback of 8 44.1kHz tracks in Sonar 3 with my new UR22MkII. The noise comes and goes, but does not occur with playback via Roland BR-800 or M-Audio M-Track (same cable on WinX-64, 8GB, i7, ASIO 1.9.6).

Here’s a sample recorded on my phone (jump to 30-sec):


Any suggestions?