I am having the same issue. It happened on my '94 Winne Vectra, too. I just had a camera and CCT repair place rebuild the board. Apparently the diodes, etc. melt after a number of years. Worked great thereafter.
I don't know about mega$ cameras. Seems most of the one's I've seen have IR. Mine does (did) and my Winne, too. I've seen new ones on eBay for very low prices.
However, the contrast knob is the most obvious and hopefully correct issue.
2003 Alpine 40FDTS (400HP)
Long Beach, CA