Disklavier

Hi Everyone, I don't post that often, had something occur today that 
has occured before and have had to call and get Yamaha to come out in 
the past and fix only to find that it is an easy fix, unfortunately I 
never write down how the technician fixes it.  I was attempting to 
play a Yamaha diskette today and when it played the notes were all 
wrong.  When the technician fixed this before he found I was somehow 
on 'Upright' Piano.  And this simple fix from Upright to Grand seemed 
to remedy the situation.  But I can't seem to find how to get there, I 
can find the 'voices' and it is set on '1' which is Grand Piano, but 
that must not be it.  Does anyone know what setting I need to change 
to fix this without my calling Yamaha out again, or having to wait 
until tomorrow to call them?