OK, finally had the time to Factory Reset.
It took about 4 hours to get it most of the way back to how it was. Longer than expected.
The only thing wrong is when receiving a phone call, the default notification sound plays, instead of the selected ringtone.
I can change the sound via the default notification setting, but the call ringtone will not play.
ETA: well, I fixed it, but definately did not follow any logic that could be repeated. I gave my office phone contact a custom ricngtone. Called the M from my desk and it played the custom tone. Selected default ringtone for my office phone contact. Called the M from my desk, BINGO! the selected ringtone played, instead of the default notification tone. Called the M frrom a phone nto in my phone book and the selcted / correct ringtone played. Go figure...
Also, I have not had the issue of the M not recognizing the Car Dock, at least thru about 10 incertions. It boots to signal in about 2 minutes vice the 4 it was taking, prior to the Factory Reset. BTW, I performed the reset thru the Recovery menu vice the settings, in the UI.
ETA: 4th morning after factory reset; the M did not recognize the car dock. This was on about the 15th insertion. Hopefully this rate of failure maitains as opposed to excalating in frequency as time goes on, as previously experienced.