midi controller pitch problem

HI,

No matter which controller I use (M Audio or Motif ES 8) the instrument detunes itself via the modulation control in MainStage and Logic both. So its like someone is turning the pitch bend wheel all the time and it gets stuck. Always tunes down for some reason. Now I called Apple and Yamaha and they both blame each other. Now the Yamaha won't do this as a stand alone instrument without midi connection. It even detunes the keyboard sound engine when using these apps as well as virtual instruments. I realize both keyboards are about 15 years old but this should not happen. The Motif is great as a studio controller and I'm used t it. I just invested in an Arturia and I plan on using MainStage live which scares the heck out of me. Someone please help.