I have an VX Signature Pro here that has strange behaviour. It appears at first to be working normally, but occasionally will be travelling and stop so suddenly that the rear rollers lift up and 'clack' down on the floor again. Often it will then say it is "determining it's position" again before moving off. It soon becomes apparent that all is not well and it starts getting lost and confused trying valiantly to find a way through a wall and then pops up with a "vision is blocked" error. If prompted to return to dock it heads off in the opposite direction and after losing an argument with another wall, the error pops up again.
Even though this is a new unit (5 months old) and I doubted the LIDAR motor is worn but I swapped it anyway. No change.
While fiddling with NeatoControl (what a great tool!!!) I noticed that the Drop sensor readings stay on 0 and the mag sensor reading does not change even if a bring a magnet close to the sensor.

While this seems wrong to me, it does not sound consistent with the above odd behaviour?
Any ideas?
Cheers.