Hi Colin, I have not had this happen to me, but I have heard of it happening before. A suggestion is to check out the battery, as a slightly failing battery can play havoc with some of the less important electrical features. If the battery is getting old or is a little discharged things like cruise control, radio etc will not function properly. I had a problem with the rear demister, which was cured by putting the battery on charge for an hour. Meanwhile, some of our members might have had the same problem and will probably be able to assist. Regards, Peter,