are there "audio outputs" (RCA) connectors on the cable box or the PS3? Maybe try hooking them up.
I have a 42" Plasma display, PS3, Comcast HD-DVR and Bose V30 set-up at home.
The Comcast HD-DVR and PS3 are connected to the Bose system by HDMI cables and HDMI-DVI cable connects Bose with the Plasma display.
I just want to be able to switch the plasma display off when using either the PS3 or comcast box for music only. Basically be able to use the Bose system in the sound only mode. (Plasma burn-in issue)
I tried using all the settings on all the three boxes but cant find a way to swtich the plasma display off and still listen to music. As soon as I switch the display off the sound goes away too, although the Bose system remains On