I've researched many posts on this site and others, and I'm still not sure I understand. I understand the Sonos 5.1 is typically set up with an optical digital cable from the TV's output into the soundbar, right?. But my TV manual says optical digital output is produced in 2-ch stereo when the source is from HDMI, so no go that way. So, why can't I just use the optical digital output from my Yamaha home theater receiver to connect to the soundbar? I see lots of recommendations to use a Sonos Connect, but I just don't understand why I would need one. I really only use 3 sources going into my Yamaha: HDMI from xfinity cable box, HDMI from chromecast (for Netflix), and 3mm-to-RCA audio from my laptop's headphone jack for music (iTunes, spotify, etc). My assumption is... the optical digital output from my Yamaha would send Dolby 5.1 to Sonos when I'm using HDMI sources (xfinity box and chromcast) and would send 2-ch stereo from my laptop headphone jack (and maybe Sonos coverts 2-ch music to 5.1 output to better fill the room with sound?). I assume the volume would be controlled from my Yamaha remote. But what would I use the Sonos app for? Just adjusting individual speaker volume to balance the surround? And my final concern is... I prefer my surround speakers mounted at ceiling height, so how do folks get power to the rear Play:1's if you mount them high like I do? (If the ac plug had a 9 or 10 ft cord I suppose I could feed it behind the drywall, but I suspect the power cord on the Play:1s are not that long). Thanks in advance for any advice.