RD-RD (+ RRD-PRO) will turn on light, but not off

• I've got an RRD-PRO and an RD-RD.
• I have tried 2 different PROs and 2 different RDs always the same results.
• I have tried swapping the PRO and the RD (though PRO was supposed to be allowed on both sides, I thought).
• At the moment the line is coming in to the black on the RD-RD, brass goes to black wire and blue to red wire. Then onto the pro. Red wire-blue. Black wire to black. Load to brass.

I've, like, triple checked this by pulling and pushing the little safety switches and track what goes hot when.The RRD-PRO works just fine. The RD-RD is able to turn the light on. It is unable to dim. It is unable to turn the light off. I can turn it on with the rd-rd. turn it off with the pro. Then turn it on again with the RD-RD.
I have absolutely no idea what to try next. Other than checking my wiring for the 17th time, anyone have suggestions?
Thanks all!

Try the following: PRO - Line to Black Red = Blue Brass to Black on RD RD- Red= Blue Black from Brass on PRO Brass= Load

I rechecked the wiring for the 15th time, even took photos of the wires and voltages as I pushed and pulled the FASS switches to prove it was wired right and was going to post all of those here. As a step of desperation I changed the bulbs. They were some band I've never heard of and put in some CREE dimmable LEDs. Now the rd-rd works just fine. It was absolutely the load. Uggh. Sorry to waste everyone's time.

The bulbs would have been my first troubleshooting step. Not LEDs are created equal and some are very problematic when it comes to dimming. Lutron has a database of many they've tested, but there more out there than they could ever hope to check completely.

I also suspect it has to do more with the lighting load than your wiring. As I found out with the old 6D dimmers when LEDs first came out, the dimmer can act normal if you go straight to the dimmer but the electronic parts inside aren't working due to the wrong bulb so remote dimmers or keypad commands sent to them don't work.

I would double check the bulbs to make sure that A. they're dimmable, B. if dimmable, which method they prefer - forward phase/reverse phase C. You're meeting the minimum load amount. Also, how are you wiring the Pro dimmer? If you don't connect the neutral in the Pro dimmer, it acts like the CL dimmers did and becomes forward phase with a 2 bulb minimum- with the neutral it defaults to reverse phase but you can change it to forward phase in the software. I would definitely try it with a neutral.

Inability to dim usually means you have the black and brass connections swapped. The PRO will work because it is directly connected to the load. It doesn't need the RD.

There are some cases where you don't need the neutral and the dimmer can go in either place but life is easier if you connect the neutral and put the dimmer at the end where the wire goes up to the light.

You are correct about the wiring method.
Black is power in (from breaker or previous device)
Brass is power out (to load or next device)
Blue is communication

I know this is probably check number 20-something but I would check the wiring at the RD. The black wire coming from the cable with the red wire should be connected to the brass.