Ok so, the update does indeed fix the rear speaker issue when your watching sky for example via HDMI however if you go to spotify and connect via wifi and play a song the rear speakers will not work.
Also tried youtube via mobile and via amazon firestick no sound out the rear speakers again.
So a bit of good and bad news. Can others who say it is working now check if it does via spotify, youtube, mobile device etc.
I don't experience any of those issues after the update. Spotify Connect works. Amazon Fire Stick 4K works fine, great on fact. YouTube native app on Q90 TV works.
2.0 content gets played as 2.1 on “standard” mode. Try playing spotify on “surround” mode.
That's what I did too. I failed to mention this in my reply earlier to another member.
I just hit the same problem and send my Q90R today back to Samsung to get a "new" one...
I am really exited to see if the "new" one works better...
I also had to disconnect one of my rear satellites, in my case the right one.
But after I did this the Q90R works perfekt with every input: XBox One X Dolby Atmos; Netflix; TV; WiFi Spotify Connection; switch in between those modes... Everything was fine, just the start of the Soundbar is not acceptable for me, not for a top product!!!