Can someone fill me in as to how this works with their audio? Every other HD program I watch including OTA HD comes across as 5.1 DD. My surround sound system is a little old, as now I see 7.1 DD is on the market. My question is, when a basketball game is in HD it doesn't come across my audio equipment as DD. Is this because ESPN is doing the "circle surround" thing and my equipment will not accept this? If there are people with the "circle surround" feature on their audion equipment can you tell me if its worth upgrading to. I am content now with my 5.1 DD system.