Skin tones turning orange and grey - Fault

[NX3]

We have Loewe 28" CRT approx 7-8 years old. The tube blew at 5 years but was still within one months warranty. It was from John Lewis so it was repaired with a new tube approx 2-3 years ago.

It has a intermittent fault which is gradually getting worse and more persistent. When watching tv white flesh tones start to turn orange and grey. It seems to only affect people who are pale white e.g on 'The One Show' Adrian Chiles turns but the female tanned presenter doesn't. All other colours appear to be ok, Question of sport was ok overall but it comes agos. Today has been bad since the news, loads of presenters colours went orange / grey! The split of orange is on bright parts of the skin, the darker tones are grey. The colour setup is pretty normal, not overly bright.

Its very peculiar problem, does anyone know what is causing it or how to fix it ? Or is it, as you'd think, just indicative of the tv dying!!!!