Once the roof aerial is removed - see previous posts on this subject -open it up via two screws at base - need to peel back rubber - what will become obvious is that there is a contact tab of metal which, when the unit is closed up and screwed tight , makes contact with aerial base - this is the problem! The contact tab and the base of the aerial needs to be cleaned and contact cleaner and possibli silicone grease applied. When closing up assy. make sure contact is adjusted to make contact with base of aerial. Re-mount aerial , using silcone grease and some contact cleaner on inside of nut and washer - this needs to be earthed. Check for "ant on" status on radio by pushing menue button for at least 10 sec. Job done. This fixed my poor reception.
