Reading other posts, tried answering questions previously asked.
I bought a brand new Roku Ultra 4670X 126.96.36.19907-46 and hooked to Visio TV E55U-D2 and experiencing audio drop outs of about 1-2 sec every 40-45 minutes. This happens on CBS All access and Curiosity Stream. It happens when HDR Subsampling is set to either 4.2.0 and 4.2.2. Audio leveling is NOT enabled. This happens on Klispche sound bar hooked to TV optical AND also happens on some headsets hooked to the RCA out of the TV. This Roku has also experienced random reboots.
This is NOT happening on a different Roku Ultra 4640X 188.8.131.5207-29 hooked to a Denon receiver in another room. That one works perfect.
My audio only dropped out for about 2 seconds but came back. I did find the resolution, i went back to the 4640 hardward build. it only happened on the 4660 hardward build. I returned the 4660 build to Best Buy and found a 4640 on ebay. But i'm still pissed off with Roku. Looking at the FireTV, had to side load Vudu so they aren't in good vibes with each other and all my movie collection is on Vudu. AppleTV doesn't support YouTube HD content. Just a bunch of bullcrap. Ultimately, Roku was still the best option.
I have two ROKU Premieres on two separate VIZIO tvs in two rooms of my house. I was having the sound drop out problem on the family room tv and tried everything I've seen in this forum, (new cable, different HDMI port, reset to factory, etc.) to no avail. I finally isolated it to a conflict with the ROKU Premieres being watched simultaneously. In every instance the family room Premiere would work flawlessly until the bedroom Premiere was turned on. When that happened, the volume on the family room Premiere would drop to a very low level for a few seconds and then return to normal. And it would happen every few minutes until the bedroom Premiere was turned off. I have two additional TCL ROKU tvs in other rooms and neither of them are affected. Anybody have this problem?
3 new ultra 4800s and having audio drop out, reached out to Roku and the Sent me a few steps to try to fix the audio from dropping out. First I turned off sound leveling, and then went to settings and then to audio and changed sound from auto to stereo, and so far that solved the problem. Hope this helps, also asked Roku when there will be a software update to fix the audio issues.