I have set the flaps to FSUIPC calibration. Which I just assigned and calibrated the flap control. No other axis I'm using are doubled up in P3D settings or anywhere else. I tried a few flights today with send to FS as normal axis and worked fine with the PMDG 737-700 So I don't know if FSUIPC calibration is causing an issue.
The throttle buttons I have assigned are Throttle 1 Dec and Control to repeat while held checked and throttle 1 cut. The same process for throttle two is done. The reverser's still activate spontaneously during taxi.