do you have x-sabre set as the default playback device in in windows? also wasapi is exclusive, so if you have jriver on in wasapi mode, no other sound will play (need to close jriver).
the audio output doesn't switch part is windows' problem, it doesnt automatically fallback to another output device when the default one is unavailable. your speakers are not hooked up to the dac? do you have surround or something? i would just hook them up to the dac for convenience (use rca splitters)
Totally didn't think of that. Good call, I'll look at the windows defaults. I'm talking about the built in laptop crap speakers haha just so if I'm leaving my desk for some reason I usually just unplug the DAC for 15 minutes and let it play with the junky laptop speakers.