All remotes are collectors of all cind of nasty things. After a while they look pretty nasty. Maybe im pretty anal with my things, but I think that a remote often is really nasty.. So I disasemble them clean them and reasemble them.
When I was ready I realized I forgot to take pictures..
This takes about 10-15 min for a Beo4.
1 Remove back cover and take out the batteries
2 Remove the 4 screws, one is (was in mine) under a sticker.
3 Loosen the cover/ lift the backcover (it almost falls apart
4 Loosen the 6 nuts
5 Now you can remove the front with the buttons. The cicuit board and display is another part. I cleaned the buttons and frontcover with warm water and soft deturgent, then I dried it with a soft cloth.
Assemble everything the same way. And the remote looks like new :)
BeoCenter 2, Beovision 10-46, BeoLab3, BeoLab4000, BeoLab3500, Beo4