My new Roku Ultra LT system surround sound is broken with the latest update (May 29, 2021). I had to reinstall my older Roku 3 model to get my Tablo recordings to again play. I tried all the settings for surround sound on the new model with NO JOY. The older model works perfectly. The update has simply broken the Ultra LT unit. No work around that I can determine.
I again reinstalled the Roku Ultra LT (Model: 4662RW OS Build 10.0.0 4198-46) to do additional testing. All my other apps Netflix, Hulu, SiriusxM and Spotify are all working normally with surround sound. I now believe the problem now lays with the Tablo app (ver 2.17 bulid 0). Its’ reporting that Roku Ultra LT is telling the app that there is no surround sound capability.
My only work around is to reinstall my old Roku 3 to watch my Tablo recordings.