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Contributor I
October 18, 2026
Answered

Beam Ultra stuck at flashing white light when using optical adapter

It was added in Sonos app successfully and can play audio after the first initial setup. However, when turning it off and on again while having the sonos optical adapter plugged in, it just stuck at flashing white light. BUT, if I remove the optical adapter and leave only hdmi cable plugged in, it would work fine (solid non-flashing white status light). Plugging in the optical adapter and then selecting the TV SPDIF source in sonos will work after this. But again, turning the Beam Ultra off and on again, it get stuck again at the flashing white color. Anyone has the same issue?  

Stanley_4
Stanley_4Answer
Grand Maestro
October 18, 2026

That is one I haven't heard  before might be best to call Sonos support and have them look at it.

Are you using the Sonos adapter or a different one?

Send a diagnostic once setup, and a second once you get the optical connection working. Then call with the diag numbers.

14 replies

Stanley_4
Stanley_4Answer
Grand Maestro
October 18, 2026

That is one I haven't heard  before might be best to call Sonos support and have them look at it.

Are you using the Sonos adapter or a different one?

Send a diagnostic once setup, and a second once you get the optical connection working. Then call with the diag numbers.

kkl888Author
Contributor I
October 18, 2026

yup using the official sonos optical adapter. I contacted support once regarding to the flashing light issue, but we didn’t know it was caused by the adapter at that time. Then they liased with local distributor and get me a replacement unit, but upon testing, it has the same issue as well. We also tested the demo unit and ended up with same result too. Total 3 units are having the same problem. So we are suspecting it’s either firmware issue or there’s a manufacturing issue that affects all beam ultra. Probably goin to contact support again for this new finding, but wanna double check again in forum and see if anyone is having the same issue. It works fine for my Beam Gen 2 though. 

Airgetlam
October 18, 2026

If memory serves, a flashing white light on the Beam Ultra has, or is supposed to have, more to do with network connection than with data connection from the TV, so I’m confused as to why it’s acting differently than described in the LED states FAQ. But as you suggest, it seems like Sonos Support is your best resource, currently, there isn’t much we can ‘do’ in this forum.

Bruce
106rallye
October 18, 2026

My Beam Ultra had no problems with the adapter.

kkl888Author
Contributor I
October 19, 2026

Wonder if you have tried switch off and then on again. If you are in a country without on/off switch on wall plug, then it’s unplugging and plugging back the power cord.

AjTrek1
October 18, 2026

Why are you using an optical adapter in tandem with HDMI input if it’s (the optical adapter) not needed? Also, what do you mean when you say “turning the Beam Ultra on/off” as there is no on/off switch/button?

Together Everyone Achieves More = T.E.A.M.
kkl888Author
Contributor I
October 19, 2026

Why are you using an optical adapter in tandem with HDMI input if it’s (the optical adapter) not needed?

What do you mean? The optical adapter suppose to convert the optical input to hdmi. It still needs hdmi cable to connect to the soundbar. It goes like this: Optical output from tv → Sonos Optical Adapter → Hdmi cable → Soundbar hdmi port. I’m not sure if we are in the right context.

 

Also, what do you mean when you say “turning the Beam Ultra on/off” as there is no on/off switch/button?

Some countries have on/off switch on the wall plugs by default. If you are from countries without on/off switch on wall plug, then unplugging and replugging the power cord would do the same. 

AjTrek1
October 19, 2026

Let’s clear this up…

Are you saying your TV only has an optical input? If so then OK I under understand your use of optical. However, if your TV has HDMI ARC there’s no need to use the optical adapter. What is the make and model of your TV.

Also on/off wall plug or not why do feel it necessary to power down the Beam Ultra?

Together Everyone Achieves More = T.E.A.M.
106rallye
October 19, 2026

This was my use case (for a week, since then I bought a Feintech AX-310 Audi extractor) too: PC to optical adapter to HDMI to Beam Ultra. Since Windows does not provide anything other than stereo I decided Ed to go another route.

​@kkl888 Did you test the optical output on your PC with another device?

kkl888Author
Contributor I
October 19, 2026

My pc has optical output from the motherboard, so it’s easier to use Sonos optical adapter.

It works with my Beam Gen 2. I also remember testing it with Bose TV Speaker many years back, and it was working since it accepts optical output directly.