896mk3 - pops, scratches & warbles

[BlueBrain]

Hey there. Trying to figure out whether this is driver issues or faulty hardware - have done about as much troubleshooting as I can. Here are the details:

896mk3 hybrid
Pops, scratches, crackles, warbles in audio playback
PC, windows 8, good specs, 8gigs ram
Drivers/software uninstalled/reinstalled
Same problem in Reaper or Digital Performer
Changing buffer or any other audio settings doesn't fix
Same problem regardless of project size (one track with no plugins)
Same problem regardless of which audio drivers are used (asio or others)
No problem with audio playback if routed through PC hardware

Can sometimes take two or three cycles of powering mk3 off/on before software will recognize it properly & allow playback at all.

Pretty frustrating. Any suggestions?

Thanks!