I changed the Digital Output to Mirror Analog from Rig Output just now, and set 11R as the default sound output device. It still doesn't output my Mac-generated sounds. The XLR are plugged into the Main Output on the back of 11R going straight to the monitors. I can hear my guitar no problem, it's just the sounds from my mac is no longer available.

I also opened Logic Pro X, with input and output set to 11R. It sees my guitar signal and I'm able to record but no sounds during playback. My Mac definitely sees the 11R but it just won't output the sounds as it's supposed to.

Anyone have any ideas what else I should check?