Originally Posted by
midal
Well it appears that it is a design fault generally.
I might have a look around and see if I can get some sealing rubber to go right around the back door, not quite as thick as the inner seal though. There is room for it, a little tight behind the hinges and by the latch but it should work and that will prevent (or at least minimise) dust from getting into the area hopefully. That just leaves the entry point under the plastic housing where the external latch is. Really do need something around those hinge holes as well though.
Cheers
Mick