Best answer by Airgetlam
If you open up the controller to the settings area, and select "About My Sonos System", what does it show on the line under the Beam that's labeled "Audio In:"?
My bet is that it's going to say Stereo, which is why you're not getting much sorround (sic). In order to get a surround signal, your input has to be set to send Dolby Digital to the Beam. That often requires changing audio settings in the TV set, and any device that you have connected to the TV set.