The video below will go through the Fenix A320 throttle calibration which is a required feature before you take off for the first time.
You'll need to go to:
MCDU MENU
CONFIG
CONTROL CONFIG
Take a few minutes and run through the calibration with our CEO talking you through the necessary steps.
Users who are experiencing IDLE REV at 0% instead of IDLE read below:
For anyone who has this issue, the solution is to go to C:\ProgramData\Fenix\FenixSim A320\calibration.xml and edit the calibration lines for the reversers and idle to zero manually. Fenix calibration had put them as 0.000333221111 etc instead of fully zero. I have a null zone in my joystick software to prevent that, but it didn't seem to matter. Do the edit for both throttles, and voila no more annoying IDLE REV.