Low to High rate changes trim of elevator
 

Anyone have this problem when I change from low to high rate elevator I have to retrim for down trim as the servos move alittle causing a slight up out of trim result.Radio is JR 6102 and servos are standard 537's.I have split with a Y harness but I also have a splitter with an adjustable pot on another plane (same type of servos) and it does the same thing.
I would appreciate any ideas on this issue.

Thank You

Fitzycrow