There are cases that are almost documented - e.g. BSI computer in Peżota. Until some time I did not believe it until I found the FF in the eeprom, probably 307. The memory almost erased before my eyes during the replacement of the battery for new - I emphasize because it could have been significant. All settings (ie car configuration) simply "checked" and I had to re-load VIN, PIN code, settings, keys ... Read about it BSI is already writing books. Interestingly, after uploading the settings, the machine works without any reservations.
The previous battery was scrap - maybe there is something in it?
So it is possible? Unexplainable coincidence - CB radio microphone. The controller has the markings scuffed, but it looks like a D8751H. I left the microphone on while it was connected to the battery and forgot to turn it off. The memory was cleared in this way for about a week before the voltage dropped to zero during that time.