Hi, just joined your lively group. I've inherited a Beomaster 1900 to go along with a range of other B&O equipment, all of which works well. Speakers came with it, with the correct connectors etc.. When I plug either speaker into the four output sockets, only one of the sockets works - and it works quite well. Everything else works perfectly, with the possible exception of the on/off switch which is a bear to push. Aside from cleaning contacts is there an obvious/simple thing I should be checking? Each speaker works perfectly when plugged into the one working socket so it isn't speakers or wiring. Thanks for any assistance you can offer. I'm happy to get inside the 1900 if I have to. Cheers, Kimo