Had a new 46WH08B delivered 3 weeks ago and spent some time getting the settings right using all the good advice on this forum. Everything has been fine until the last couple of days. When I first switch the set on after it being off for a while (e.g. overnight) the convergence has gone wildly out. It gets a little better over the next 10-15 mins and then suddenly everything is OK. It is almost as if a switch has been operated. Since it was not previously doing this (and I haven't been messing with the settings for a while) I'm wondering whether I need to get on to a service engineer. Anybody else had/having this experience??