You’d need to turn off CEC on the TV, as CEC only allows a single speaker ‘sync’ device. 

You should read that as ‘it’s not easy’.

Ah right and if CEC is turned off then I can't alter volume on the beam via the TV remote ?? Can you alter volume via the Sonos app ?? 

Correct. CEC carries such things as audio from the TV to the speaker, and volume controls. However, when you turn off CEC, the remote for the TV should control the volume of the TV’s speakers, and the Sonos controller would control the volume of the Beam, if it is playing anything. 

Thanks , so if I connect the beam via HDMI and turn off CEC I'll loose the ability to control the beams volume via TV remote .....but I can control the beams volume via the app ! 

I won't loose anything else if I turn off CEC ? 

Thanks again 

Well, normally, you’ll lose the ability to play the TV’s sound via the Beam. You’re essentially turning off the ability for the TV and Beam to communicate with each other. At that point, you should have purchased a different speaker than the Beam, which was intended to work with your TV. You could still use an optical connection to the adapter, which then would plug in to the Beam, but so far, all your posts seem as though you don’t want to use the Beam to play anything from the TV. 

I suspect this may depend on the TV - in my case I can’t use both the TV speakers and a connected Receiver/HT device at the same time, nor can I output audio over HDMI-ARC, if the CEC option is switched off. So the answer maybe to just try these things.

I wouldn’t choose to have audio output from both the TV speakers and a separate connected Soundbar/Receiver anyway, as I suspect the output from both, would ‘likely’ not be in sync and would cause an echo in the room, but perhaps okay if switching between the different outputs, but I personally never bother using the TV speakers as the Beam sounds great for the many TV/Music audio formats that it supports anyway.

Not at all , I want to use the beam for movies and music but the wife doesn't want to use it just when watching her soaps , 

So if CEC is off will I get sound from the beam ?? 

You will likely find the TV requires CEC to be ‘on’ for connection to an audio Receiver over HDMI-Arc/eARC, such as the Beam …and CEC will need to be ‘off’ when playing through the TV speakers. At least that’s how my TV’s here work from both Samsung and LG. but you can always switch the Beam to use the TV’s optical port Instead, if you prefer to leave CEC ‘off’ permenantly in which case that allows control of the Beam using infrared instead …and CEC is irrelevant for an optical connection. You will still get Dolby Digital 5.1 surround audio with that type of setup.

Note, if you leave CEC switched ‘off’ on the TV, you will not be able to control any ‘other’ HDMI connected devices to the TV using the TV remote - so if you have a cable box, fire-stick, Blu-ray player, PlayStation etc. attached to the TV, then you will have to resort to using their own assigned ‘remotes’, rather than a single TV remote.

Thank you for your reply , I get it now lol I only have sky HD ( not sky q ) their movies I think are Dolby 5.1 ?? I was thinking I may get better audio via the hdmi than I would using the optical ?? 

Worst case is , is that when the wife watches her soaps I go in TV settings and turn off CEC , when I want a movie on I turn on CEC , I presume iam correct saying that ? 

Yes.

While it will not support the 18Gbs 4K formats (mostly used for gamming), this device will block the CEC communication while allowing the TV’s CEC to be enabled.

So using one of them it will stop the sound coming out of the bar but you can still use the remote on all devices via CEC ? 

CEC (Consumer Electronics Control) does not transmit audio. Evidently, when your TV receives a CEC communication from BEAM, it assumes that audio should be sent to BEAM. Using the CEC blocker will prevent BEAM from communicating with the TV and the TV will continue using its internal speakers, yet continue to communicate with the other CEC devices. Unfortunately, this will also block Volume CEC commands to BEAM. You can always use a SONOS controller to adjust BEAM’s Volume or you could train BEAM to respond to IR Volume commands from one of the remotes. Don’t use the TV remote for this because it will then adjust Volume on both the TV and Beam.

Most IR remotes provide an option to control Volume on an A/V receiver. You can pick any model and train the remote and BEAM to use these Volume commands. Give the same A/V receiver model to any remote that you want to use -- except the TV remote.