Let the hive mind of Engadget get that for you.
"What is the best wireless surround sound speaker solution? I have a home theater where running wires is just not feasible. I have my own speakers, so I don't want a system that has speakers with integrated wireless. I've done a far amount of research and have only come across a few companies that even offer a reasonable solution: KEF, Kenwood and Rocketfish. Is there anything else out there? What do you recommend? Thank you!"
It's a pain to have the PC and TiVo on the LAN? Really? This works over the network, no direct connection.
As for doing it on the box - see my above comment about why they didn't do that.