Hi,
My Samsung SyncMaster 955DF nearly always powers up with the red color missing. After warming up for a while it usually comes back. If I get impatient and smack it up-side it's head, it will often begin working but usually blinks out again unless it's warmed up.

Is there any adjustment inside the case that could make this situation better? None of the on-screen controls seem to help.

Thanks,
Jim

I think, it is bad CRT, (maybe short between red cathode and heater or G1 - check this, but it usualy causes one color very bright) or weak Red cathode. Check also bad soldering.