Missing surround sound after firmware update for QN95B to v1640.9

[Alexey_RND]

Hi everyone!

I'm owner of TV Samsung Neo QLED QN95B (2022) 4K Mini-LED.

It's connected to my home theater system via A/V Receiver Denon by S/PDIF (optical) connection (HDMI is not available here). In Samsung TV Sound settings I set AUTO mode (not PCM, BYPASS is not available w/o HDMI connection) and selected OPTICAL output (not TV SPEAKERS). Sound goes to TV and then to AVR and connected speakers.

For a year I used the firmware v1430 and sound from AVR was fine (coded and decoded successfully): multi-channel sound, DD, DD+, etc! After update (yesterday) to firmware v1640.9 multi-channel sound is gone! (stereo only). I re-checked this on my different devices for exclude non-TV (firmware) issue. Also, i tried to reset sound settings with no effect.

I have a single way for odd bypass of this is to change OPTICAL output to SPEAKERS and back. After that multi-channel sound is returns. But this is not a solution as in the case of a single glitch. Because after TV turn-off and wait sometime and then turn-on it this issue is come back and need to do all again. It's annoying!

I believe that somewhere hidden some kind of sound setting which is reset after switching off and after my manipulation it is temporarily overwritten to its normal state.

Any ideas for resolve this issue? (need help) Please, not factory reset for just to check..

May be somebody faced with similar issue on other TV models and/or firmware versions?

Thank you!

[Alexey_RND]

Unfortunately, there is no positive news for a fix of my problem.  Hope, that future firmware updates smhw to resolve it even if its a single case. 

I'm pretty sure the problem is that when the TV turns on, the TV SPEAKERS setting switches to OPTICAL output only visually but not logical. Thus, i have sound from my AVR (not TV), but with stereo decoding (not surround) similar as for TV speakers mode (PCM). It is possible that this is also due to the fact that in the Smart Hub view removed the ability to change the video mode (Standard/Movie/Filmmaker) and other visual settings (available when a specific source is displayed).

[Alexey_RND · Accepted solution]

My temporary solution that may help someone else: After turning on the TV, open the quick settings panel and switch sound output from OPTICAL to SPEAKERS and back. No matter what setting was before. The surround sound should back!

CHEERS everyone and Thank you all!

[jopi1975]

Sounds like my issue. It just randomly keeps reverting to TV speaker output, and many people was having same issue back then. This issue was however solved in a firmware update late last year, and was then working perfectly fine. But now with last update the exact same issue is back again. 

This is really annoying, I thought Samsung had some clue about this issue but seems like they just randomly manage to fix and unfix this. So bad 😞