right the tv is getting the audio from the hdmi cable. You are running an optical cable out of the tv, I have not seen a tv with an optical audio out from it. the dvr is not working for audio because you have it from the tv to the sound bar like you posted earlier if I read that right. So if you look at the back of the cable box there is a little door there for the optical out, do you see it lite up in red? that would indicate that your box is working for the optical out. You can also use the red and white rca outputs to go to the bar.
If I were you heres what I would do. Run the red and white composite cables for sound from the box to the bar, run an optical audio cable from the dvd to the bar, That should be fine. You would want the best sound when watching a nice 1080p movie from the blue ray in my opinon. also what do you have have the audio settings set to in the box menu>?
Thanks for the suggestion, I'm going to try to run the optical straight from the box, to troubleshoot if the DVR is bad. But that doesn't explain why the Blu-Ray works and the DVR doesn't. Like I said in the original post, the TV is getting the audio successfully, if I use the TV speakers. Switching the speakers off and using nothing but the optical out, produces no output to the soundbar from the DVR...
The other problem is the soundbar only has one optical input, and I have 2 sources Blu-Ray and DVR...
Blu-Ray player (HDMI 2) > Toshiba HDTV (TV Optical Out) > Insignia Soundbar
Audio and Video signals reach the TV successfully and if I use the TV speakers I have sound. While I'm on HDMI 2 (the blu-ray player) the soundbar receives the optical signal successfully, however while I'm on HDMI 1 (the Comcast DVR) the soundbar doesn't produce any sound.
If I switch back to the Blu-Ray player I have sound, swith to the DVR no sound.
I went through the DVR audio setup and didn't see anything amiss.