To be serious: I haven't seen color degradation on a PV+ screen. When I've seen damaged cables or failing video drivers, it's been color lines or squares of screen that have gone blank or inverted; standard damaged video stuff.
Do the discolorations appear to be along pixel borders, or are you seeing more natural borders or blotches ?
Any trouble with the touchscreen sensitivity ?
Anything interesting about your installation ? Humidity, unusual chemicals, pressurized cabinets or stresses on the bezel might cause the LCD to misbehave.
See if you can get Bruce MacDougall (North Coast) or Brian Rootham (RA) to come out and see it with their own eyes. They're fair about warranty issues, and if this is a production quality problem they'll want direct feedback to get to the factory.