My apologies for not answering sooner.
The screen has deteriorated further, now being un-readable.
While considering the age of the KN, & the use we have had out of it, we decided to purchase a new keyboard.
We now own a Yamaha PSR S-950. As we regularly use both keyboards (Tyros 4 & PSR) for the dances we run, we need the consistant reliability of the instruments.
As well the PSR will be able to be used as a back-up keyboard should the Tyros fail on a night. Having similar operating systems & filing, it should make life easier should the need ever arise.
We use the Tyros as our main keyboard, while the PSR is used as a harmony keyboard only.
Once again many thanks for your interest & help Bill.