Seems like I'm Mr Unlucky then. I have an Express and a Premiere, both with the same 16 apps installed and I've tried every suggestion in this thread to no avail. 15 apps have always worked flawlessly, but Prime Video always has video out of sync when watching films (TV shows are often OK strangely). I've resorted to using an old Sony blu-ray player downstairs and my PS4 upstairs instead which never have issues. Annoying!
There have been many previous posts that suggest there are several different issues identified on this board and while some solutions may work in some instances there is no silver bullet. Like the previous post I have a ROKU Express and despite trying all of the suggestions nothing worked. My sync issues started 18 months ago and if anything the issue got progressively worse when I received additional software updates. The fact that ROKU is now offering a $20 upgrade to a newer model for existing owners suggests to me ROKU knows about the issue and is not able or willing to fix it in older Express models. I have 3 newer ROKU TV's and so far I have not seen the out of sync condition. I also have a Fire Stick and have never had an issue with out of sync audio.
Mine lags too. It didn’t lag initially but now it does after about 3 months of use. All channels lag. I have an LG TV, not a Smart TV, no sound bar. Anyone find a solution? I’ve tried changing the audio to “stereo” as someone suggested and it didn’t make any difference.
2 streaming sticks, premiere, ultra. All on different makes of TV. Ultra hard wired the rest WiFi. All players have lip sync issues on almost every channel. Without a doubt a Roku problem they are ignoring. Time to try trading standards and from there wherever is needed