I use my Bose bluetooth headphone daily. Never had a problem on my macbook pro or iMac.
I updated to Catalina 10.15.1. Now randomly the computer switches from headphones to internal speakers. It isn't clear if the headphones are disconnected, they still show connected under the bluetooth list. In the sound preferences I can select the headphones, but it doesn't affect the sound, and if I close and open the sound preferences the internal speakers are selected. I have to disconnect and reconnect the headphones to get it to switch back to the headphones.
I have restarted a bunch of times.
I have disconnected and reconnected.
I have removed and added the headphones as a bluetooth device.
I have deleted the bluetooth plist files in the library (/Library/Preferences + ~/Library/Preferences/ByHost ). and restarted.
I ran Apple Diagnostics, it showed nothing.
I reset NVRAM (per Udhy), still have the problem.
Any other suggestions? Thanks.