http://www.kv32tweak.freeuk.com/
take a look here, there's a useful forum jam packed full of things all about this model.. some of it applied to many other Sony's to...
Are you talking about purity problems at the extreme edges of the screen or all over?
I assume (as you know about purity!) that you degause the TV only when turned off at mains for an hour or more then turn on. Or better still, degause with an external degausing tool.
No speakers too close to the TV?
