Yikes, you done the reset and it still is going bonkers.
That is the problem with modern gear, it has enough memory and processing power to accommodate stray malcontent spirits!
I think you need to find a good exorcist!
But, seriously, I am at a loss. Sounds like you need to return it.
I would initialize it about 3 times in a row (I don't know why, but this worked for me in one instance) just to be sure, and if that does not stabilize things, you'll get a chance to see how good your local guy supports you (he should have no problems if he is an authorized dealer, because Yamaha will take the hit, not him).