USB ports do everything except export music


Am I missing something here? My iMac has several USB ports but none of them will allow me to play iTunes/PM through them. The headset/Toslink outlet is the only way I can run music through to my system. A year or so ago I could come out of the iMac USB port into the Pop Pulse and then on to the system via SPDIF. Now that doesn't work.

Maybe there is a setting that I have forgotten about?
puerto
I suppose it's possible that the USB audio output of the iMac could be not working while the rest of the USB functionality is. It's also possible, of course, that the USB input of the Pop Pulse isn't working while the optical input is. You'll need a different computer or a different DAC to sort that out, though.
I think you are right that the audio output of iMac is not working (USB ports). Thanks Sfar!
I wasn't saying that I think the USB audio output of the iMac isn't working, in fact I think that's unlikely, but you won't be able to figure that out without testing with another computer or another DAC.