Disklavier

Hi 
    I have a Mk3 DU1-A Disklavier which I have to say is superb in 
every way . Just recently one of the keys has started to stick 1/4 
to 1/2 way down when playing a midi file from my laptop or  a file 
from the controller . If i press the key manually it comes back up 
again by itself until said note is played by computer again . Is 
there some sort of adjustment/calibration I can do myself or is it 
going to be a job for a technician . Your help with this would be 
much appreciated as the manual doesnt really go into much depth 
regarding troubleshooting . The piano is just about 10 months old 
now . Thanks  Great site by the way .

                Tom