Simple Sample not tracking above C6

[SteveR]

Hi good forum folk,

Hope you can help me resolve my issue, which hopefully is simple User error, but driving me nuts :)

I have a FG6 and finding that when I create a simple patch, using a single sample, it's not tracking the full length of the keyboard. It seems to be ok up to C6, then every note above is the same 'C6'.

Is this a case of needing to re-set back to factory or is there a simple setting I've overlooked?
Any suggestions gratefully received.

Thanks, Steve