Hi. Not been on the forum for a while and I think I had the same problem before but I forgot what I did!
Just got home an hour ago and I wanted to watch some TV before going to bed and there's no sound from the TV
However if I go into Amazon Music then whatever song I am playing works fine.
I have tried both resetting my router and unplugging all Sonos products but it's still not working 
Any help would be very welcome.
I forgot to say that Sonos radio also works.
I just noticed that on the Sonos Arc section it says: Audio In: No Signal
Moderator edit: removed picture with serial numbers
All of those point to an issue with the TV sending a signal to the Sonos for it to play. I’d start by unplugging the TV from the wall for two minutes, then plug it back in.
Then, if that doesn’t jump start things, I’d check the TV set for any updates, and apply them, and finally look at the CEC (or whatever this manufacturer chose to call it) settings on this unknown make/model of TV set.
Hi Airgetlam.
My TV is a Panasonic 65JX800 and I did check for updates but I already have the latest software for my TV.
I did however run the TV self test (using the built in TV speakers i.e. NOT the Sonos Arc) and I dont know how, but the Sonos Arc is working again!
I'm so pleased as I can't get used to the built in TV sound after hearing the Arc!
Thank you for your feedback 
Hi
Power off the TV as suggested by
Hi AjTrek1,
I did check the HDMI cable but no damage.
I can only assume that the TV self test somehow 'kickstarted' the sound from the TV to the Arc although exactly how this happened is beyond me
Sounds like a reset of the CEC communication across the HDMI cable, caused by the TV reset. Glad it’s working!
Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.