Sometimes, a remote requires calibration because stuff gets caught between the plastic bezel and the glasstop screen.
With the 9400, there is no chance of stuff getting between plastic bezel and screen but might not hurt to reset the ribbon cable connectors. ;-)
It might be worth it to disassemble and remove/reconnect the glasstop from the circuit board as well as to clean out stuff that might have fallen into the unit around the hard buttons or scroll wheel.
Just be careful when disassembling as the page up/down buttons on the side have switches behind that are surface mount contacts and you risk damage of pushing them off the board if not 'handling with care'.
