Ya I would nix the A/V receiver and run your video sources direct to the tv and their audio into the Lyngdorf. Keep it simple. Think about adding a second sub configured for stereo. The idea that deep bass is monaural is not true. Also introducing bass from a second location usually evens out the bass response in the room. Try to put one sub near each speaker. One other tip for better imaging is to cover the TV with a heavy blanket when listening to music. Having a highly reflective surface between the speakers can mess up their ability to create a 3 dimensional image of the performance.
You will be surprised how good an experience can be had with a two channel theater system. Much simpler and less expensive.
You will be surprised how good an experience can be had with a two channel theater system. Much simpler and less expensive.