Hi.  From Sonos article on setting up rear surround speakers.:

• Products used as surrounds will connect wirelessly to your Sonos home theater product. Make sure they are in the same room and have line-of-sight to your home theater product.

So with the Amp in another room it isn't surprising that you have experienced problems.

I am not sure that "line of sight" is totally precise. The HT product and rear surrounds communicate using a direct 5GHz link, so that needs a strong and stable signal. 5GHz isn't great at wall penetration. So "line of sight" does seem a reasonable description. 

You would connect the ARC port of the TV to the HDMI port on the Arc soundbar, then wirelessly pair the Amp with the Arc for surrounds. If you are able to have the Amp in the same room as the Arc, this will be beneficial because the Arc transmits a private WIFI signal for the surrounds and Subs to connect to. There is no need to use the optical output from the TV for this.

Hi @tenminutes, congrats on the amazing Bravia 9!

You definitely want to connect your Arc to the Bravia’s eARC port. The (optical) TOSLINK-to-HDMI converter is a compromise intended for TVs that lack an eARC/ARC port; you would lose CEC for integration/control and compromise stability. The Amp ‘should’ work fine bonded to the Arc using the dedicated 5GHz link.

This is super helpful.  Thank you!  May I ask one more questions since this is clearly full of very smart people?  

IDK if this 2021 Samsung TV has an HDMI Arc output.  But even if it does, my Sonos Playbar doesn’t have this output…

That in mind, if I were to go purchase a Sonos Arc and connect the TV to the Arc with HDMI Arc, would volume control be reading from the eye of my samsung TV or the Sonos Arc? 

For context:  I built this hidden soundbar shelf and made a speaker grill for it.  It looks cool, sounds great, but totally blocks the connection from the samsung remote TO the soundbar eye.  For four years the only way I can adjust the volume is on the app, which is sorta a pain in the butt.  But it was my own doing to disrupt the eye from the Playbar to the Samsung eyes.  

I’m just curious if the connection of the HDMI Arc allows me to control the volume from the TV eye or if my issue would still remain (and has nothing to do with the optical OR the HDMI) ?

This may dictate how I set up my new living room too.  Thinking I’ll just do a white Arc visible on the wall next round and stop being so crafty 

 

This is super helpful.  Thank you!  May I ask one more questions since this is clearly full of very smart people?  

IDK if this 2021 Samsung TV has an HDMI Arc output.  But even if it does, my Sonos Playbar doesn’t have this output…

That in mind, if I were to go purchase a Sonos Arc and connect the TV to the Arc with HDMI Arc, would volume control be reading from the eye of my samsung TV or the Sonos Arc? 

For context:  I built this hidden soundbar shelf and made a speaker grill for it.  It looks cool, sounds great, but totally blocks the connection from the samsung remote TO the soundbar eye.  For four years the only way I can adjust the volume is on the app, which is sorta a pain in the butt.  But it was my own doing to disrupt the eye from the Playbar to the Samsung eyes.  

I’m just curious if the connection of the HDMI Arc allows me to control the volume from the TV eye or if my issue would still remain (and has nothing to do with the optical OR the HDMI) ?

This may dictate how I set up my new living room too.  Thinking I’ll just do a white Arc visible on the wall next round and stop being so crafty 

 

 

From your initial post, you have the impression that you had the Arc already, therefore the recommended solutions were for that speaker. With this added information here are new answers related to your setup:

1. Yes the volume would be controlled from the TV because you will set up the output to be the Arc.
2. The flush mount opening will actually compromise the Arcs performance. You will lose the Dolby Atmos functionality and the side firing speakers will be useless.
3. The Arc needs approximately a 4” clearance at the top for the up firing speakers to work properly.

From the Sonos Arc user manual ...

Keep 4" space (minimum) between the top of the soundbar and the bottom of your TV (if placing soundbar below the TV).

… the above specifically calls out the distance from the top of the Arc to the bottom of your TV, which is far less acoustically restrictive than a wood enclosure.

Placing the Arc in a ‘cubbyhole’ will kill the upward-firing Atmos speakers and create reflections. I strongly suggest choosing a soundbar without upward-firing Atmos speakers.