Please try the following to solve this issue:
1.) Quit DPS by clicking the DPS “B” icon in your top menu bar.
2.) Pair your Bluetooth Device with your Mac.
3.) Pause any audio that might be playing.
4.) Restart DPS
5.) Select the Bluetooth Device from the DPS Output Device menu.
Please feel free to email me directly at firstname.lastname@example.org if this does not solve the proble, or if you have any further questions.