Unfortunately the problem you describe is one of the symptoms of the notorious "lens cap" image sensor defect, and which would have qualified for a special JVC free repair as the model mentioned is on the list of models susceptible to developing the problem, "would have" being mentioned as the free repair offer was only valid up to the end of June 2009 after having been running for nearly three years, the qualification on receiving the repair being that the person requesting it had to be the original purchaser of the device and have proof of this fact, the "original" purchase receipt being the usual item shown although credit card receipt proof can usually also be accepted. Of course its not completely unknown for JVC to "sometimes" carry out a goodwill repair without this, but it all depends on who deals with the request, as this qualification was made to stop dealers buying up defective camcorders on the cheap, getting them repaired free, then selling then on at a profit. If you meet the original ownership qualifications mentioned I would contact JVC customer services on the UK phone number of 0870-330-5000 as you have nothing to lose as they might oblige, however if they don't then the sensor doesnt cost the earth but its a case of getting someone used to working with precision equipment to fit it for you, plus them being good at soldering as approx 14 very finely spaced IC pins have to be soldered to replace the item.