What is your source Antenna or actual Cable?
Question for you:
Do you get your HD through the air broadcast signal or was it through a digital cable box?
My TV is plugged in directly to the cable (no digital cable box) and the HD channels I pick up are the regural air broadcast HD, using the reciever built in to the TV.
In addition, I don't have a dedicated antenna plugged in, it just uses the cable itself as an antenna (hope this makes sense) and I actually don't even pick up all the HD availible in the area because of that.
What's your connectivity like?