I've moved this from Kev T's post as it was starting to interfere with his. I seem to be having a problem with my week old W177 as nothing seems to connect to any of the USB sockets. I'm using the C to A adapter as supplied by the dealer and when I connect a memory stick or my phone through it I get the message "no device connected". I've checked the fuse (123) and it is fine. The only thing I've done is to wire in a dash cam to the cigar lighter /socket (fuse 124) which is working fine. Can anyone tell me if I am in fact checking the correct fuse?.