My client has some Elation Platinum Wash ZFX Pro units in a permanent event space install. I do an annual maintenance sweep for them. Last year a couple of the units started to flicker when they get close to full on (R, G, B, W emitters all at or near full). If you take the edge off and lower some intensities, the problem goes away. I replaced the LED driver boards in both units and the problem went away.
Fast forward a year and the same two units are showing the exact same problem. All the symptoms seem the same and still point to the driver board IMO, but I just replaced those a year ago, so it seems the problem must be deeper. Units went from ~28000 hours to ~33000 hours in the last year (users often forget to kill the relays and they sit idle for months sometimes).
Only clue I have found so far is that the LED driver boards on the problem units are getting slightly less voltage than their fully functioning friends (~27.1v vs. ~27.5v). The bus is supposed to be 28v and power supplies in all units meter at a solid 28.1v. The only thing between the PSU and the LED driver board is the P/T motor board. So, one theory I'm entertaining is that the motor board is drawing too much power leaving the driver board underpowered and that the new ones were able to cope with the underpowering for a while.
I've definitely seen this exact same issue in several house rigs at various concert venues around the country, so I'm hoping perhaps someome on here has cracked the issue.
Thanks internet!