I have a Bose USB 2.1 system. When I plug it into my MBPr directly, I have the option to output sound to "Bose USB Audio" and it works beautifully. I just got a new monitor, (a Dell U2415,) and if I plug the speakers into the USB ports on the monitor, it doesn't show up as an output option. I'm trying to set up a home workstation that I can plug in and out of easily – I would love for both the speakers and monitor to work with just the mini displayport plug instead of having to plug/unplug both the mini displayport and a USB every time.
Why don't the speakers work when plugged into the monitor USB, and is there a way to fix this?