I have a Sony KDL-46XBR6 and would like a discrete code for the speaker toggle command to turn the TV's internal speakers on and off. I have 2 Harmony remote controls, an 880 and the Ultimate Home. I use the 7.7 software to program the 880 and the Android app or myharony for the Ultimate Home. The plan was to use the 880 to teach the Ultimate Home, unless there's an easier solution.

I also have my cable company remote. An AT8550 from Brighthouse Networks.