Squeak,
I'm at home this morning. I just called my tech support buddy at Yamaha, explained what you are experiencing, and he will call me back at my store at 10AM with a definitive answer.
Again, I sure wish you would have bought your 550 from me so that I would be doing this investigation for you as my customer.
So the rest of you may understand my position here, Squeak asked me for a price quote and I did my rather lengthy explanation as to why I hoped he would buy his PSR550 from a dealer such as myself, because you never know when you might need our assistance, and sure enough, just a few days after receiving his 550 from a mail order store, Squeak is asking for this kind of assistance. I hope for all reading this post that I don't come off sounding angry or upset, because I am not I assure you. You all know that I enjoy sharing my knowledge with all who request it if I can help. I know it's been an ongoing conversation around here the past few months, and as a Dealer, I've tried to post my point of view as to when the price is close, go for the dealer who can really help.

George Kaye
Kaye's Music Scene