Jasbur,
I can't guarantee that this is the asnwer but my 6300 stopped working properly, in just the same way as yours, just before Christmas and, on examining the unit, I discovered that one of the soldered pads to the charger socket had pulled away from the printed circuit board. Whilst the unit continues to charge up it does not pick up satellites. This leads me to believe that power is not getting to the relevant part of the receiver.
Like you I tried Evesham and they couldn't/wouldn't help me and, an independant retailer said he didn't think it could be repaired.
The only way you can see if your's has suffered the same fate is to remove the back cover and check the charger socket carefully to see if your sat-nav has suffered the same as mine.
Good luck and hope this helps.
Regards,
Graham.
Graham Percival
January 2008
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