B& O Beolab 6000 problems

Hello there,

I have some problems with a B&O system I bought. I have a Beosound Ouverture and I just bought one (only one speaker) Beolab 6000 active speaker.
After I connected the speaker to the power supply everything looked ok - the red led lighted.
I connected the powerlink cable from the ouveture to the Beolab 6000 speaker and it seems the ld doesn't go green. It seems that the audio signal from the ouverture is not passed to the 6000.
I have switched the bottom button of the beolab to be left speaker and then right and nothing happens. The speaker led remains red and no music is heard.
My question is... it is absolutely necesary to have two speakers in order that the system to work ? What can I do to use a single beolab 6000 speaker with the beosound ouverture?
Any advice should help.
Is it the cable ? Is it the speaker ? I have tried all the posibilities and no result till now.
I am getting desperate...please help if you know.

thx a lot,
Stefan