Has it always dropped memory settings like this even when it was new? That is very strange. I have never heard of a keyboard with digital memory doing this before. That is why they always have an internal battery to hold memory when the keyboard is powered down. Maybe the battery in it is flat or has always been faulty.
It would be very inexpensive to replace it to see if that is causing your problem. You would just have to open the keyboard to find it on the circuit board somewhere.
[This message has been edited by Nigel (edited 02-07-2009).]