I've noticed this happens occasionally to my Slimpar56 and even my brand new intimidator zoom/wash fixtures. My first guess was that it had something to do with the order in which the fixtures were powered up, and turning on the power to lights after turning on power to the DMX controller. Then I switched to Chauvet ShowXpress DMX software and was able to correct the issue by switching scenes and switching back to the slow fade scene.
But then I noticed the problem still occurring and was able to isolate it to a faulty DMX cable/connection on the fixture itself. The connection was intermittent causing the fixture to fall behind the rest (even if it was in the middle of the chain)
First I would make sure you are using true DMX cables. And second, I would make sure to check all DMX in/out connections for solid conductivity.

Interesting. I am 100% using DMX cables. I know that for a fact. I keep them separate purposely.

Ill try and check the connections next time I hook everything up and see if there is an issue there. I did have a problem a few weeks ago where half my setup was acting all funky. Had a bad DMX cable which I threw out, but that doesn't mean I have another problematic one in the bunch.

I had the same issues with my Chauvet Color Strips (minis). I have to use master/slave connections if I want them to perform identical functions... DMX has all kinds of odd issues.

Try putting a terminator on the last in line (120 ohm resistor across pin 2 and 3) as you get what's called 'backsplash' using standard mic cable can have strange effects on the ground because your using the shield as a ground. Depending on what software or desk your using try addressing them separately as see if the speed /fade time is then matched, cheap dmx boards can 'throttle' when sharing the same address.
Just message me if you need any help, it's my day time job

2 times I set up my lights this way I had a terminiator once and the other time I did not, but still had the same result.

I am using DMX cable and not mic cables so that's not he problem.

I did just order a DMX splitter. Aside from making things a little easier to set up, maybe the shorter runs will help out a bit.

I am using Show Xpress. Ill keep you posted when I have time to retest with the DMX splitter and I will certainly PM you if I need help!

Thanks

There could be your problem, software like show xpress and in particular Chamsys sends dmx at very high speed and generic dmx boards have problems processing at that rate, try adjusting your dmx output rate, acme and chauvet and the generic heads like that can suffer from slight lag usually milliseconds but enough to get pissed about even though people don't realise when watching.
Mixing different heads especially some of the higher end Chinese gear can make you think the pan and tilt is on elastic but adjusting output you can find a happy medium as most decent makes will operate with any rate.
Good luck and make sure your splitter is individually isolated 😉

I assume I can adjust the DMX output rate within the software. Obviously not something I am familiar with.

Yes, the splitter I got is individually isolated.
Someone else on another forum I posted the question to suggested doing a factory reset on my fixtures to ensure there isn't any funky settings I may have hit at some point that could also be throwing it off. I am going to try that as well.

What dongle are you using? I have Enttec DMX Pro and DMX King dongles for Pangolin software. I like the DMX King one better because of the processing rate and throttle control built into the drivers. Enttec is good and very universal for almost all DMX applications, but it can act screwy with certain software.

Using the Chauvet show xpress dongle.

Also to rule certain things out, (if you haven't already tried it) I would suggest moving the rouge fixture to a different place in the chain and see if that makes any difference.

Yea, going to try (if I have time this sunday) to do all the trouble shooting people mentioned, different wires, different order, terminator, reset to factory settings, try to snap to colors instead of fades to see if it happens there as well.

I think the signal may be getting transmitted properly because I didn't notice any lag at all in my moving heads, just in the leds.

DMX splitter will also be arriving today which is how I will be hooking up my lights in the future so I will see if that helps also.