This is not a question but a possible solution to the Roku Ultra audio drop out issue some are experiencing. I have a Sony XR77A95L for the TV and a Sony HT-A9 for the surround sound system. I just got both in March 2024. I also got the Roku Ultra (in June 2024) because my Roku 4k streaming stick the voice search stopped working and it was getting so hot that the sound was distorting. Unplugging it and plugging it back in only worked several times at removing sound distortion and it eventually died. Incidentally, you should get an extension for your Roku streaming sticks (and I think they're free) because the streaming stick can get hot and possibly damage the HDMI port on your TV. Get them at: https://my.roku.com/hdmi
So, my audio was dropping out like crazy with the Roku Ultra. It made shows unwatchable and it didn't matter the app I was using whether: Netflix, Hulu, Paramount+, or even Philo. I went to Audio on the Roku Ultra and tried adjusting the Preferred Streaming Format from Auto to Dolby to DTS. I also tried adjusting the Digital Output Format from Auto to Passthrough to Stereo to Custom and even tried adjusting that setting so that DTS was set to on. I couldn't get the audio dropouts to stop. I even unplugged my WiFi power cord and plugged it back in (resetting it) to no avail. Still had audio drop out. The only way I was able to stop the audio drop out was to change the setting on my TV to PCM (Pulse Code Modulation) instead of Auto or Passthrough. Incidentally, PCM is used on CD and DVD players. So, no more audio drop outs. But now I had a new problem, no Dolby Atmos, DTS:X or even dd+. See, PCM is only going to give you stereo 2.0 or 2.1 sound (left and right 2.0; left, right, and sub 2.1). You won't get 5.1 or 7.1 on PCM. This was unacceptable for me with this expensive setup. I wouldn't be able to take full advantage of my setup and abandoning the Roku Ultra for a Firestick or an Apple 4k streamer just seemed more like a gamble. Would I encounter the same problems with either of those platforms? For those that think the grass is greener on another platform think again. People are complaining about the same audio drop outs on those other platforms as well. And I know there would be buyers remorse if that happened on the Apple 4k streamer because it's just more expensive than the Roku Ultra. So what's the answer?
I ordered a High Speed HDMI 2.1 cable from Amazon for around $15 bucks. They have certified High Speed HDMI 2.1 cables and others that aren't certified. I bought one of each but the first one I tried was the one that wasn't certified. I changed the setting on my TV from PCM to Auto. On my TV I can go to settings and then go to Detailed Signal Info that tells me if my picture is in 4k and what the Sound Codec is. I was getting dd+ immediately. So, I went to the Audio setting on the Roku Ultra and set Preferred Streaming Format to Auto and then set the Digital Output Format to Auto, and voilà. When I checked Detailed Signal Info the Sound Codec showed Dolby Atmos. My system now works and all I needed was a new High Speed HDMI 2.1 cable. This is a cheap fix but could possibly solve all your Roku Ultra audio drop out issues. Hope this was helpful.
Thank you for reporting your success. It should be a great help for others.
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