In safe mode there is no beep. The sound is not the default notification sound. It is the sound when you plug in the phone. I really do not want restore phone to factory.
Edit for Update: Simply putting the phone in safe mode then restarting the phone into normal mode seemed to fix the issue for me. At least for the last 10 minutes. Big thanks to all who suggested this resolution it was driving me crazy!
To put the phone into safe mode:
1) Press and hold the Power button.
2) Tap and hold Power off (on the screen).
3) When the Reboot to safe mode prompt appears, tap again or tap OK.