Hey Dom, Not sure what could be different it could be that the RNS which now does the diversity for the antenna isnt as good as the seperate box or doesnt boost the signal. It doesnt matter it was a potential cheap fix will fit a shark fin and do as recomended by Apollo13 and put the full aerial under the roof in the head lining and see how that goes, as a longer term solution I will have to look at the second rear window aerial once I have chance to remove the trim.