Hi,
In the end, I contacted AV-Sales to get them to investigate the high-pitched noise. They were very understanding, but rather than ship endless new screens they agreed to collect the screen for testing and collected it within a few days. They tested the screen against their demo model and a new screen and felt that my screen noise was no different to the normal Panasonic.
Not 100% happy with this outcome, I asked AV-Sales to ship a replacement plasma anyhow, which they did, as they wanted me to be 100% happy. I received the plasma and after most of a day testing, the noise is no better at all and the picture is actually slightly worse than my previous model - go figure!!!
So, over the next week I decided to go and look at some local demo Panny 6's and see if mine was comparable on the noise front. After seeing two other demo Panny 6's I have realised that the noise made by my screen is actually pretty normal. Maybe I am just unlucky and tune into the noise more than others...Maybe I have been a little over critical...
IMHO from what I have seen, no Panny 6 is completely silent and once run in for a while, they all emit a very similar high-piched noise which varies with screen brightness. Whether other people can hear this from their normal seating postiiton is the key and also whether they are able to tune into the noise...so for people out there looking to get the Panny 6, just make sure you are happy with the noise level whilst demo'ing BEFORE you buy.
Anyhow, AV-Sales have now agreed to ship my back my original plasma...who knows, maybe in a few years when they say Panny plasma's are silent, they will be!!!!
AV-Sales have been incredibly helpful throughout the entire process and have been above and beyond the normal call of good customer service, especially the out of hours time they spent on testing, let alone my endless chasing phone calls!!!
So a big thanks to AV-Sales for all their help, especially Andrew Collie - AV-SALES - A HIGHLY RECOMMENDED DEALER
JJ