Beam: Keeps switching back to ARC from Bluetooth - how to stop?

It must surely be an LG issue, because it all works fine on their C9 OLED TV and it works on an older 2015 LG TV we have in our Home too. We just disable Simplink to use the other TV outputs, like Bluetooth.

There is one other solution I can think of …and that is to purchase a Sonos Port/Connect (gen2), add a Bluetooth transmitter to its line-out and group it with the HT room - I have the Port and can confirm it works okay too and is fine (for me) for lip-sync purposes (unless I just happen to be lucky in that regard)… I just quickly tested it with this cheap transmitter: 

https://www.amazon.co.uk/dp/B07J58KY3X

I did consider the Arcana but with the shield it would be nearly 25% of the system cost again for slight convenience. If there were no alternatives, I would settle for disabling eARC, CEC, using headphones & then changing it all back again rather than cover that additional cost. I just have a get out of jail free card given Sonos’ excellent returns period. I was happy to accept enabling/disabling CEC from the quick menu but any more than that is asking too much.

I’m not sure adding a port & grouping it would be an effective solution. It’s the same headset I use with my PC and it’s not unusual my other half is watching TV & I’ll be using my headphones through the PC. I’m not 100% sure but I imagine it will involve more messing about to swap to and fro.

For what it’s worth I’ve emailed LG support today to ask about it. I’ll update with their response. 

I have the same issue as the OP with a Samsung TV.

Seems like the Beam must be sending a constant signal over CEC to force the TV to switch back to it. I thought that CEC would only change the input when a device was first turned on.

Annoyingly this even happens when the Beam is set to output something other than TV. This makes for a poor user experience

Might be worth reading the Wikipedia entry for CEC . Sonos doesn’t really control that system, they just implement the API as it is agreed upon/written by others. 

Sure, but switching inputs is a single CEC command right? So Sonos must keep sending that command. Either that or Samsung is switching input based on some other CEC feature. 

It’s been a while since I read the full CEC spec, but I think, if I remember correctly, its not a turn on/off signal, it’s a “is a client present” or “is a client not present”, matching what you initially suggested in your post.

Which is why, if you read a bunch of the threads about this, folks suggest turning off CEC on the TV set, so it’s no longer looking for the client’s existence, particularly for folks who are trying to add a set of headphones. But it’s the CEC controller, i.e. the TV set, in charge, as opposed to any particular client, such as Sonos.

Interesting, thanks for the response!

I did find this page (https://www.samsung.com/us/support/troubleshooting/TSG01111222/#turn-off-automatic-hdmi-switching-with-smart-remote) which suggests it's possible to turn off the automatic switching without turning off CEC, but it had no effect on my TV. 

Yea, to be honest, it’s been seemingly hundreds of years since I did any actual electrical engineering, and much of that was before the existence of CEC, so my understanding of the spec is probably rudimentary at best. 

The joy of the whole thing is that there doesn’t appear to be any “enforcement” function in the spec, so each manufacturer has modified it slightly (in my most humble opinion) to match their own needs….giving priority to their own hardware over someone else’s. So it wouldn’t particularly surprise me that a feature that works on one line of TVs may or may not function on a previous year’s, or different line of TVs. 

It’d be nice if we all played well together, but that doesn’t work for many companies, who want to maximize their own profit over being easy to use with a bunch of random other hardware. Yea, I’m cynical that way :)

Always happy to share my (tainted) views. Having previously worked for Sony (albeit in a games division), I’m always fascinated by the frisson between “we need to work with everyone” and “we need to have/own Betamax/DAT/MiniDisc/ATRAC/MemoryStick/UMD formats that are under our control, and no, you can’t use them without our express consent”. From a corporate perspective, I get the “our company needs to own the market place”, but from a user perspective, I much prefer the “I can use X from company Y, and Z from company AA, and they’ll work well together”. 

Shoot, look at how none of the various networked speaker companies, including Sonos, allow you to mix and match in their home theater products :)

This is a pretty disappointing issue to have encountered with my Sonos system.

This was not an issue when using my old cheap Yamaha sound bar.

Temporarily disabling HDMI-CEC does work, and I have found that you can add this toggle to the “quick settings” in WebOS (appear when you single click the gear icon⚙).

I read with interest that Samsung might let you disable automatic HDMI switching and I hope that LG implements this. I personally would prefer to select an input rather that have it automatically selected.

If this issue is a “feature of the CEC spec” then there something is really broken I the spec.

Hi @alephsmith 

If you read @Airgetlam’s post closely (just above yours) you’ll come to realize there is “no spec for CEC implementation”. What that means is unlike Bluetooth or  WiFi (802.11 a/b/g/n/ac/ax) there is no governing body that sets the standard.

Long story short the implementation CEC is not broken as there is no spec to break. It’s an open technology (and may be taking a few liberties with the aforementioned wording) that TV manufacturers incorporate into their products in a manner that best suites their needs.

So a fix as you stated would take a gathering similar to the United Nations for TV manufacturers. LOL 😂 

That said… one can only hope 🤔