Bluetooth Issues with MacBookPro 6,2 (Mid 2010)

I recently replaced my elderly MacBookPro (late 2008: 5,1) with a slightly more up to date version (Late 2010: 6,2). While using it, I noticed a very odd problem: Audio over bluetooth headphones started out clear, but would degrade over time to a very low bandwidth quality. (Speech would sound robotic and unpleasant).

Audio over wired headphones or the MacBook speakers was fine, so it wasn't a problem with the inbuilt DAC or the audio sources. My Bluetooth Headphones (Jabra Move) can also be used wired, so the problem was not with them either. (And also, playing audio over Bluetooth from a phone didn't exhibit this problem, so the headphones were not the issue.)

I tried the following procedures before find the correct solution:

• Unpairing and Re-Pairing the headphones. Problem persisted;
• Restarting the Mac. Problem Persisted
• Restarting the Mac and Clearing the PRAM/NVRAM (CMD-OPT-P-R on Boot). Problem Persisted;
• Reset the SMC: (Power off, CTRL-OPT-Shift-Power button, Power on) Problem solved!

I don't know why the SMC reset worked, but my theory is that the Bluetooth Module was replaced at some point, and the SMC reset forced some re-reading of the low level devices in the system.

I didn't find any useful info when searching for a solution, so I've written it up here to help anyone with the same problem.