I keep getting an intermittent MSG. Stating
(An external disturbance was detected on force sensor 2. The heat bed plate may have touched something outside the heat bed. [0300 0b00 001004]. )
Does anyone know what to do about this.?
Clean out any loose bits of filament trash in the chamber, especially around the three z axis screws.
Remove any accessories you may have added, like plate alignment guides or poop chute covers.
Sounds un-Jedi-like to me. 
But seriously, are you getting any strange grinding noises? If not, this would be one of those rare occasions where I might suggest as a last resort, performing a baseline calibration from either the slicer or if it continues, doing a factory reset from the printer menu.
What the calibration should do is to rebalance and recalibrate the vibrational harmonics of the plate. You may not remember but that was the escalating pitch you heard when you first calibrated.
Two questions out of curiosity. Did you by chance calibrate your printer without the build plate? I ask because that’s an easy oversight to do when the printer first initializes out of the box. Also, did you change build plates perhaps to a heavier 3rd party plate or are you using the factory supplied version.
Perhaps a long shot but make sure there is nothing near by that could introduce vibration, such as a machine, fan, whatever. Even sound waves from a speaker, especially a sub, can cause movement. A friend mentioned in his shop they could see parts produced on a lathe had surface finish and dimensional inconsistencies and it was due to a tumbler machine on the other side of a wall.
I suspect my build plate guides were causing this issue. Frustrated I didn’t think of this sooner, thanks for proposing this as a potential solution.