Even with a hardware bug, I think it could be cured with a software update. Clearing the cache (for example with Netflix) cures the problem for a while. I suggest that code could run to clear the cache whenever the TV is put on standby.
Right, I've sent this to Sony and hope that it has some effect. If lots of us did the same they might take notice. My message to Sony - 'This is not a query but a suggestion. Pretty-much all Sony TVs that have Dolby Vision capability have a glaring fault (even the absolute top of the range Sony TVs) in that after some hours of watching in Dolby Vision, the colours start to go wrong. The only ways to stop this is to clear the app's cache or reboot the TV. The problem is stopped for a while but returns. This is my suggestion. If, when the TV is put into stanby, a small code ran that cleared the cache of any Dolby Vision apps it would solve the problem. A software update that included this would put an end to this glaring fault of Sony TVs.'
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