I have a 3-way Lutron dimmer switch installed at the end of a 4-way circuit in my home (there are three switches controlling the lights to our 1st floor staircase, 1 downstairs and 2 upstairs). I don't know anything about circuits or switches; I just follow directions. That said, I'm pretty confident it's wired correctly.

I have read online (on this question, in fact) that for a 4-way circuit you need to install a 3-way dimmer switch on one of the ends. I've tried both ends (one of the answers to the above question claims it matters, though the top-rated answer asserts it doesn't), but either way the switch works but only dims lights to about 50% when the dimmer is all the way down. All the other dimmers I've installed in the house take lights down smoothly to pretty much 0% when the dimmer is all the way down, so I don't think this is working like it's supposed to.

Am I making some simple mistake? Is this a fundamental limitation of putting a 3-way dimmer switch on a 4-way circuit? Does it have anything to do with the number of lights on the circuit, or the distance between the switches (like I said, they're above and below a staircase). Or do I most likely just have a defective dimmer switch?

In case it matters, one other potentially relevant piece of information: most of the bulbs on the switch are dimmable LEDs, but there is one incandescent bulb in the middle (replaced a recessed can light with a pendant light). Not sure if that could be responsible for screwing everything up.