[sgroup] QUESTION ON THE ROLAND S-10

I have been playing around with my ROland S-10 and have just created a simple 514K sample of a bass guitar in Band D. I have no other sample, and after pressing F1/F2 there don't seem to be any splits or anything else. The problem is that my sample plays nicely across the first3 octaves of the keyboard then on the final octave the pitch repeats the second last octave rather than continuing to go higher. Im guessing this is either a really word problem or some simple setting that Ive missed. Any help much appreciated….Given there is no split and only this single bank loaded I just can't figure out why my first 3 octaves are fine and this last octave is a near repeat of the second last octave. Thanks Jon