Arc stops working with TV , was working fine

You stated that “the same cable works with other devices”. Unless you’re talking about other ARC devices, there are unfortunately some cables that were produced before the introduction of ARC and don’t have the necessary connections to do ARC, as required by Sonos. And it’s even more unfortunate that most cables aren’t well labeled. I’m almost at a point where I want to throw away many of my HDMI cables, which are HDMI 1.2 or  HDMI1.4, and not HDMI 2.0 or HDMI 2.1, and replace them with newer cables. But they work fine for video, and I’m such a hoarder…..

The cable that was originally in use was HDMI 2.0, which should be arc compliant. Again, it worked for months before the unplug/replug seemed to throw it all off.

The other cables I have no idea, so true they could just be the wrong kinds. It was more of a last ditch effort by trying to replace each individual part that might be causing the errors. 

I’m going to order a new cable now just to be 100% certain it is not the cable before moving forward.

I don’t know if anyone remembers the old school N64 or even earlier Nintendo systems. But the red white and yellow cables would always be difficult. You would have to jam a Lego piece a certain way so the male and female parts would catch and you would get picture and sound. That’s exactly what I did with my arc and it started working again. I pushed the hdmi cable in and bent just slightly so a better connection was made to the Sonos HDMI port. I used a rubberband to put some tension on it and give it tgat slight bend. Hope this helps!