Try going to:-

Programme Menu
Part Setting
Scroll through Part 1 & 2
(You should now be at LEFT part)
Check to see if the Key Shift is '0' or whether it matches part 1 & 2. If not, take the necessary action to clear it.

Also the 'Pan' setting could be different, making either/any part sound higher or lower than others.

Another area to check is the 'Expand Mode Filter' Look at page 2 to see whether the 'transpose' matches all parts. Maybe a part has been altered from a previous setting and forgotten about.

Worth looking at anyway - hope this helps.

Aud (U.K.)