All of sudden last night, the Roku Express connected to my Samsung Smart TV via HDMI cable stopped any sounds. I have an external speaker connected as well. No sound was coming from any device connected to the TV when the Roku was in power. The only option I had was to unplug the Roku Express and the problem resolved. Fast forward to today, it happened again! Twice within 24 hours! Not acceptable. The Settings screen says the last update was yesterday (July 16, 2020), so I suspect the last update is causing the problem. And judging from other posters in the last day or so, there may be a bug in the Roku Software Update. What can Roku Support suggest we do?
I started having the same problem on my Samsung TV with my Roku Express that started after my last update in June. It occurs daily! I have to go into Settings, System Restart to get audio back. And sometimes I will get a static/rumbling noise in which I have to restart. Frustrating. I hope someone has an answer. And in the meantime Roku needs to figure out the problem and fix it.
This is so frustrating! We have 3 tvs this suddenly started happening too. Roku TV, Vizio, Samsung. Like you, I am usually able to resolve it by unplugging the ROKU device but it is happening more and more lately.