Mk3 interior rattle/rumble with Soft Top up.

[MickAP]

Baffle described as flaps in the link below. They block any road noise transmitting up the drains. They are just inside that outlet under the car as shown, one each side

MK 3 Drain Holes

Roof drains eventually depart via a plastic tube on each side containing a non-return flap to keep out the road noise. Here’s a pic of the one behind the driver’s seat. There is a grille behind the seat which collects the water from various tubes depending on soft top or PRHT. Search the forum for many threads on the topic of keeping the drain clear by only ever rodding down from the top (trombone cleaner), never up from below (which damages the flaps), also noisy drains (damaged/stuck flaps)…