Which universal remote are you using? Have you tried Remote Central?
Right now I'm just trying to get some basic commands from my Onkyo to my cable's learning remote and vice versa. I'm looking around now for a new remote, probably a Harmony One but untill then, I'd like to at least be able to watch TV and change the volume on the receiver with just one remote.
And I just checked Remote Central (after your suggestion, thanks for that) but I couldn't find codes for my cable box or the 709.