Hi there,
You just have to setup both products in the correct mode (video 1 for the BeoVision, audio 1 for the BeoCenter).
Press "std-by+list" at the same time on your Beo4, then press "list" until your reach "option", press "Go", then you have "v.option"on the screen, simply press 1, and do exactly the same thing for "a.option". Then the video product will only respond to video commands, and the audio system to audio commands..
Reunion Island is greeting you!