Might want to make sure it's actually a composite connection as opposed to maybe component. Because what you describe would make perfect sense if it was a component connection.
I just bought a 2005 BigGames home arcade. The CRT monitor which is basically a TV was connected to the system by RCA's had burn in on the screen so I put a Sharp Aquos LCD TV in and used the same RCA's to connect to the system. I now have a clear picture but with no color. I hooked up a PS1 to the TV to check for color and its working just fine. I also re-checked the arcade with another CRT TV and that's working just fine. Any help would be great.

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