I have never heard of this problem. Questions:
1. Are you manually moving the sliders to the ON and OFF positions, or is it in AUTO and the programming is controlling it? If using AUTO, please post the programming.
2. Did it used to work properly and just now started having this issue?
3. Did you buy it used? Perhaps a previous owner opened it and modified the wiring.
4. Have you tried updating the EB4 software?