Make sure there is NO Excessive Heat in or around controller. If There is, try opening panel door and allow controllers PCB on back of door to have a little distance from High Voltage Wiring in panel.
Make sure the Sensor Wiring Path is away from High Voltage Lines or Equipment that may cause interference.
If Sensor wiring is going thru walls or along walls, make sure there not going thru with cords or power lines that may cause interference.
Make sure your ballasts have RFI reducing Chokes on them?
Re-position DISM Sensor Module from its Present Location do direct connect with sensor without extension cables and see if problems persist.
You can also restore the controller to factory defaults - see if problem persists.
Check Your Firmware and make sure it is current.