I am seeing the same thing. Just watched Godzilla King of Monsters on HBO Max. Got halfway through the movie and no sound. Switched HDMI cable to go directly into TV instead of Soundbar - still no sound.
Had to restart the device to get the sound back.
I have a Polk Soundbar, and it appears that the sound signal dropped from the Roku Ultra(2020) to the soundbar (green light on soundbar disappeared)
I get Pink Screen of Death on Hulu plus at least once a day.
Can you please provide more information about the issue you are experiencing? Is the issue you are experiencing only happen on a specific channel or does the loss of audio happen on all channels? Have you tried using another HDMI cable to connect your Roku device?
With more information we will be able to assist you further.
At this time, I have only experienced this on HBO Max. I am using UltraFast cable, and the channel was fine for just over an hour of the movie. The sound just stopped. At that point, I swapped so that the Roku was going directly into the TV, but sound was still not coming through. I rebooted the Roku, and the sound did come back.
I was having an issue with the sound "glitching" intermittently using my Roku Ultra that was routed through my Yamaha AV receiver. The fix for mine was to turn off ARC/CEC in the AV receiver settings. I haven't had a problem since.
My issue has been fixed. Roku agreed to swap out my 4640 with a new 4660 and I haven't had an issue since. My sound on the Roku is set to Dolby/DTS and my Roku is connected via HDMI to my 5.1 home theater receiver which is then output to my TV via HDMI.
Seems like a lot of the responses have been about different audio issues, but mine is the same as the original post. My Ultra has been working fine for months and then suddenly this week no audio. I get the startup sounds for YouTubeTV, but nothing for the programming. Doing a reset from the menu always fixes it. I was actually thinking of buying another one of these, but I’m not willing to reset it every time I want to use it. Clearly this is not an HDMI cable problem. Can we get some response from Roku?