Popping noises when sound output is bluetooth receiver

I have a bluetooth receiver connected to an old Kenwood stereo receiver. I set my sound output to the bluetooth receiver. When I play video - either quicktime or on the web - both the start and stop of the video cause a popping sound. This doesn't happen when the sound output is set to iMac speakers.

The same problem occurs when the mac os sound effects are set to play through the bluetooth device.