X52 lossing calibration

[WWSitttingDuck]

I can fly ROF for hours with no issues.

 

But if I fly BoS for 20 mins or so, my joystick looses calibration.  Throttle and yaw stay fine, its just pitch and roll that go astray.

 

Top of picture shows where it is when I start flying, bottom of picture shows where it is after 15 mins of flying.

 

Any suggestions?

 

Have updated drivers to no avail.