Mainstage Problem (detuning sounds, transposing in error patches)

I have been using Logic Pro on stage for many years and have just tried to run mainstage along side Logic in a live scenario. Logic pro runs a track and then mainstage is used to play a selection of patches whilst the track is playing. Both applications work together seamlessly and mainstage easily opens the patches, the problem is mainstage is detuning the chosen patches by a semitone and therefore I have to play a semitone lower in order to play with the backing track and this gets very confusing when jumping between software and hardware sounds!

When I play with the same midi controller through a channel strip in Logic pro there are no problems, however when i jump to using mainstage there is a problem.

Has anyone else encountered this? Any fixes?

Many thanks in advance.

Cheers,
T