Well that just ADDS to the mystery of why your system isn't working.
Now I question the Termination plug, the Cables and its wiring in the Daisy chain....and even the source of Audio driving the lamps.
It works fine when one is connected, but not fine with all four connected, and it worsens when terminated.
Take the termination plug off temporarily....Set Switch one ON in the master. 2, 3 and 4 set switch two ON and then set switch 10 ON on only TWO of those units.
Try the CA8 not only in the master....but go to the other end of the chain and connect the CA 8 there....I don't know why but I thought I saw something about the master being at the END of the set of lamps.
I'm putting all my questions into this Photo --
And I think the one thing that bothers me most is the fact the standalone lamp syncs itself to music, but they are very vague after that simple statement...
Check ALL cables involved with connecting the units. Pin 1 to 1, 2 to 2, and 3 to 3.
Check the Audio output cable to the lamps too. I would THINK the XLR outs on your Soundboard would be standard