Rainsoft Question: Gold and Silver Series Units Together

Any advice would be greatly appreciated. . .

Background: I moved into a new house that has a RainSoft Gold Series Water Conditoner unit in tandem with a RainSoft Silver Series water filtering system. Both the silver and gold series units are connected together (the piping). The Gold Series unit functions as should however the Silver Series unit does nothing. On the Silver Series unit, the dials do not turn, there is no noise from the unit, and if I try to manually initiate regeneration it does nothing. However, if I turn the reset knob that will initiate the backwash/rinse cycle, however the knob will not move, so I have to manually spin it to shut it off. . . but at least I know there is power to the unit.

Since I can't manually spin the timer knobs I am wondering if this is by design and the Gold Series unit is acting as the master controlling both. . . but then what is the point of the silver series unit? I have not seen information pertaining to this specific configuration so any thoughts or advice would be greatly appreciated.

Thanks a bunch.