My Roland VR 09 suddenly going out of tune at the performance

[Stone]

I have got a Roland VR 09, and at our last concerts with my band, it was going out of tune when i change the sound (that sound was in tune before and later too). That happens like 4 or 5 times at the last 3 concerts.
Any idea what's happened?

 

[happyrat1]

Pitch bend wheel needs to be calibrated, cleaned, and/or replaced.

Gary

 

[kiskadar69]

Maybe it's because D-BEAM is turned on.

 

[Briggy]

Have you accidentally saved the patch whilst you have the keyboard transposed. I made that mistake once.