Try running "powertop", press tab until you are on the "Tunables" page and find a line that starts with "Good" that talks about USB and/or Bluetooth. For instance "Bluetooth device interface status"

Select those lines and press "enter" it'll temporarily disable that power saving settings. I'd start with disabling all "autosuspend" of usb and bluetooth. If that works reenable some until it stops working!

If that fixes it, you can make things permanent later.

Putting the bluetooth dongle on an extension cable and disabling the HDA powersavings fixed all audio weirdness with bluetooth for me.

Of course, a lot of it depends on your physical set up.