KD-55A1 Audio Problem After Oreo Update

[mighty_fanc]

Since today's (2019-02-09) firmware update (to PKG6.5830.0205EUA), I have been unable to get any audio from my TV. I have an audio system connected via optical digital cable, which used to work fine, but now cannot detect an input. I tried all combinations of PCM / auto 1 / auto 2 outputs, DD / DD+, cache clearing.

I switched the audio output to TV speakers, but still cannot hear anything. Oddly, the TV app (aerial) does give audio through the TV speakers, but is set at a constant volume and doesn't respond to mute and volume commands. No other app e.g. Netflix, Google Play, Kodi, VLC, results in any sound. I have tried a full factory reset, but still have the problem.

[Itom86]

Same issue here. I have a turtle beach stealth 500 wireless headset, connected to the TV (usb dongle + optical cable). The only resolution for now that I've removed it completely. If there is a chance for you to connect the soundbar via HDMI, you should try, doing that should solve the situation. 

The problem is on Sony's side, hopefully they'll push out a new update soon for all the sound related issues.

[mighty_fanc]

It's at least reassuring to know that I'm not the only one - there are plenty of other posts with similar sounding issues. Unfortunately there's no HDMI input to my audio system, it's a Logitech Z5500 - which is pretty old now. I also have a pair of Turtle Beach 520s with the same issue(!).
This could be a good excuse for an upgrade - had my eye on something like a Sony STR-DN1080 for a while...