I have similar issues with a late 2012 MBP when playing music to Bose headphones, sometimes airpods, and external speakers. I thought it was interference from other bluetooth devices. Trying out your recommendation, though I didn't remove Bluetooth PAN, I just set it to 'inactive'. We'll see how that works. I also went through all the network services and set all of the ones I never use to 'inactive' as well. Thanks for the post.