Hi @ruggierom, welcome to the Sonos Community!

Sonos doesn’t auto-mute at any point, so something else will be causing this to happen. The best way to check would be to submit a diagnostics the next time this issue happens and reply here with the confirmation number. I can then check the diagnostics to see where the mute command came from.

I would also recommend reaching out to our support team for some live troubleshooting, as they have the necessary tools available to helps assist you in resolving this.

I hope this helps!

It seems to happen if I mute the TV and then don’t unmute it for more than ~ 5 min. Sleep mode perhaps? When I go the the Sonos app it shows as muted. Once I unmute it in the Sonos app then the TV can mute/unmute it normally.

I sent diagnostics and had a support call with Sonos tech support. They said it is “remote interference” because I was using both the Apple TV remote to control the TV and the TV remote to control the TV which controls the Arc. So now I only use one remote and the problem still happens every time.

To me it seems that either the TV is not getting the signal to unmute or vol+/vol- despite the screen showing the command and the light blinking or the Sonos Arc is ignoring the command.

In any case I still have an issue.

Sonos support then said it was because I was using the Apple TV remote and that if I just use the TCL remote the issue won’t happen anymore. So...I did did that but still have the issue.

Any idea on how I fix this? Just keep calling Sonos support and saying that the thing you told me to do does not work?

Maybe just see what happens if you switch off infrared in the Sonos Arc room settings in the Sonos App and just use CEC control of all the A/V equipment 

Thanks, that is a good suggestion. I tried it but it didn’t make a difference. I removed the AppleTV from the chain but that made no difference so I guess it’s something between the TCL TV and Arc via CEC. The TV is indicating that it is sending the signal but I can’t tell if the Arc is receiving it/ignoring it.

Sonos support said I need to call TCL to see if I have CEC set up correctly. I will try that but there is just an on/off switch. It looks like I have the latest firmware. Seems like it takes about 5 min of it being muted to go to “permamute”

Thanks

It’s not the TV, it’s Sonos. Happens with Sony and some other TVs as well. Happens with my Beam. Clearly Sonos goes into some sort of sleep mode after being muted for some amount of time, and ARC/CEC commands do not wake it up.

I am having the exact same issue. TCL QM 8 connected to a Beam via arc. No matter what remote I use if muted more than 5 minutes I can not unmute unless I use the sonos app. This has been very frustrating. My previous TV was a Vizio and never had this issue. I'm wondering if this TV completely cuts off the arc port when muted so much so that the Beam thinks nothing is connected and does go in to a sleep of sorts.

What did Sonos Support say, when you called them with a a system diagnostic?