Hi, I've noticed that the rubber insert in my 106 driver's side roof gutter is missing the angled tip at the leading end, so that it doesn't slip down behind the windscreen seal. When it rains, the headlining in that area gets damp (in extreme rain, the footwell gets water in). Would this bit of missing gutter be enough to cause that? If so, should I try sealant or get a new rubber insert? Views appreciated.