I have a 3 way switch and a 3 way dimmer switch to operate two recessed fixtures, which worked fine for years. Now, both spots are dim. Doesn't matter if I use the switch with dimmer or 3 way switch without dimmer. The slide dimmer works to dim the lights, but the maximum brighteness using either switch is about 30%. Is the issue the dimmer, and it needs to be replaced, or possibly something else?