This might sound crazy, but bare with me. When I replaced an aerial BASE in my old 205 with a brand new item & reattached the aerial wire, I had even bigger reception problems! It turned out that me over-tightening the nut that holds the wire in, had caused the problem. I slackened it off a bit, & hey presto.............. Weird French electrics, I guess!!!

Take the interior light out & see if the Mk4 has a similar set-up, maybe??
**DISCLAIMER** I've never looked at my Mk4 aerial base so I apologise in advance if this post isn't going to help one bit!!
