Thanks Keith - I will try again with the workshop and pass on your suggestion as to the possible cause of the problem. Many thanks.

Not really a technical person, alas! Can follow a manual, but limited experience with electrics and electronics. And except for a screwdriver and basic stuff, no equipment. Is there an easy way to check if this is a power supply problem? The fact that the problem exists at home, but could not be duplicated in the service firm's workshop, may be

Hi Keith - Thanks for your prompt interest. It is actually the picture itself that is wavy - there are no superimpoosed lines. It is as if the picture is presenting itself in a series of sine waves but only at the sides of the screen. The centre of the screen is not really affected. The movement lasts 90 seconds and gradually the picture stabilises

I am experiencing a problem each time I start up my Beocenter 1 TV. The picture is distorted with wavy horizontal lines which traverse up and down the screen mainly at the sides of the screen and these distortions disappear once the set has warmed up after about 2 minutes. The distortion occurs on terrestrial and satellite reception and on DVD from