Arc sound stopped on LG G4

I have the same problem with my Sony Bravia / Arc at times.  When it happens I hold the power button on the Sony remote until Reset appears.  After the Reset the sound comes back.  Not good to hear it also happens on an LG TV.  Are you using the Sonos pack-in HDMI cable?  I’m using a third party brand HDMI cable.  I’ll have to dig up the Sonos cable to see if the handshake failure goes away.

My other two Beam 2 bars with a Sony & LG have never failed the handshake.  Both using the pack-in HDMI cable.

I had this with an Arc Ultra on a LG C5 after the last webOS update on the TV (week or so ago).

Although I didn't try any other playback first, a simple off/on of the TV and it has been fine since...

🤞you have done what was needed!

No I'm using a high spec Green hdmi cable. Maybe I'll see if it's still in the box! 

Factory resets are typically a last resort and only recommend in extreme circumstances at the behest of Sonos Tech Support. If there was an issue with your Arc the Factory Reset erased any information that would have been useful in a diagnostic to Sonos Tech Support. If the issue returns run a diagnostic, make note of the reference ID (don’t post it in the community) and call Sonos Tech Support.

Your issue could have been a handshake issue. Sometimes a hard reboot sequence may resolve the issue:

1. Pulling the power cord while TV is on
2. Hard reboot of Arc
3. Giving the TV power again
4. Powering up the Arc

Music playing through the rear speakers in a Sonos HT setup is normal (ambient or full stereo *). Unless you’re saying no sound was heard from the Arc. Was that the case? If so you need to run the diagnostic and call Sonos Tech Support as the Factory Reset did not fully resolve the issue.

 * Music volume such as Ambient (soft) or Full Stereo can be set in the App.

Thanks. No sound was heard from arc before I reset it. How do we do a hard reboot?

Will do diagnostic if it stops again. 

Pull the power cord.

Remove power to the Arc, by means such as by unplugging it.  A pull on the cord might dislodge the speaker, causing it to fall onto the floor. (Sorry to be pedantic!)

Also, that’s a reset, if I interpret “hard reset” correctly - ie a factory reset. Reset advice is here:  https://support.sonos.com/en-us/article/reset-your-sonos-product
 

You might check with Sonos support, following a diagnostics report, before the factory reset? 
 

LOL, yes, don’t pull on the power cord. I guess it’s something we say on this side of the pond for removing power. I would unplug the power cord from the power strip/surge protector, actually. It’s easier.

Better yet, use the switch on the power strip, if it has one.  Not that I haven't yanked the power cord before.  I remember one time I had a foot on the wall and my hands on a big old shielded cable, yanking the power on a 4 million dollar peripheral video renderer that was grinding a very important OLTP system to a halt.  I pulled the power, let the industrial sized power plug drop to the floor, and as I walked out past the boss who designed/configured the peripheral I uttered "Fixed it!"

Geeze guys 😂! I guess I’m just too old for this. Really… pulling power is interpreted as “yanking” on the power cord itself. Glad I didn’t say “cut” the power. Lord knows what would have happened then. 😵‍💫

Also, the OP said they Reset the Arc. As “toggling the TV and Arc on/off didn’t work. Since there’s no switch on the Arc to toggle I didn’t get into semantics as to what the OP meant. Reset in my Sonos speak refers to a Factory Reset.

As long as I can remember a Hard Reboot meant removing power to a device while it is still powered on. Which is the same in Sonos-speak (as well with a TV) which is not a factory reset. Hard reboots merely clear a cache and/or memory but does not take the device back to a virgin state as would a factory reset.

Just to put a point on things … I’m pass Three Score and Ten. Which probably qualifies me as grandpa (at least) to most in the community. Old school to the max 😂😂😂

OK so to clarify, I toggled the various options on / off on the app. 

I think powered off the TV and arc. Did sod all. 

I then reset. A full on factory reset 😁 

Like my Sony Bravia the LG has a similar process to reset the TV without loosing data.  Like the Sony it’s something like holding the power button down for a period of time at which point the TV reboots.  My Sony Bravia fixes the “no sound” issue using that TV reset process every time.

If power cycling the Arc is also required Sonos should provide a way to do that from within the Sonos app.

We used to have a reboot option in the :1400 menus, it went away in a Sonos update. It was handy to have in some situations where the reboot was needed but unplugging was difficult. I ended up adding remote power switches to all my difficult Sonos devices.

It depends on which side is failing. Most of the time, it’s the TV that is failing to accept the ARC handshake. In which case unplugging the TV from the wall for two minutes reboots the TV, as most of them don’t have a ‘reboot the OS’ feature built in. 

If it happens to be the rare case of the Sonos not negotiating the handshake, even after a reboot, then Sonos should be looking at the data in the diagnostic. You should never be resetting the Sonos, unless instructed by Sonos support, which will mean they’ve gleaned all data possible, and are willing to lose any ‘local’ data stored on the device.

And you should always be checking both the TV and the Sonos for updates to the OS that runs them.

Ask yourself "How can I make this worse" and the factory reset (except when specifically given by support as a solution) is usually the best answer.

I had sonos when the app was pony and had to reset every other week haha 

I've had Sonos, long before there was an App, never needed a factory reset outside the Sonos noted issues.

Okn the other other hand, resetting the App or even just forcing it to stop and restarting it has been needed multiple times.

Still missing my reliable, simple and usable CR-100s.