Since we aren't mind readers, it would really help to learn the make/model number.
If your HDTV can do digital optical output, you might be able to connect it this way. The whole situation is a bit of a mess though.
I recently bought an HDTV with built in wifi channels like hulu and I have an existing AV receiver. How can I connect the HDTV to the receiver so that I hear the streaming channels through the home theater?