This started after the FW update a couple of days ago. Music Streaming in through ROON and Opt-in is working without out issue. I've got more testing to do. I run a PC into the TV and also a cable box and carry those signals out to the Ultra via eArc. This morning watching YouTube vids was painful. I haven't tried the Cable signal yet - yesterday watching hockey was fine..... I'll report back after I've had an hour with the TV using the box, then go back to PC input and cross compare
Just to be sure, I am asking, is the eARC on the TV turned on? (You will need to turn it off.)
Also, make sure your TV's digital audio output is set to PCM. (Ultra can receive Dolby, but PCM will have more stable audio.)
You mentioned that you have not changed any settings on your TV, but please check again.