Hello. Couple of weeks ago I noticed there is a problem with charging. Tomtom 6250. The sat nav just turned off while charging via windscreen holder and the satnav was really hot. It's overheating for some reason. I can not charge it via windscreen holder . I bought new windscreen holder with new USB cable but it didn't help. I can only charge it if connected directly to micro usb at the back of the satnav. Thank you for any advice.