I'm not having volume issues with Paramount Plus, but getting error messages on some programming. So I've switched over to my PS5 which works flawlessly. We recently did the same with NBA TV, which was giving us a strange audio error and not loading.
So after a year of dealing with relatively minor Hopper Plus issues, the app issues have pushed it to the trash pile. Going back to using the Fire Cube and ordered a 3rd Gen with the HDMI input for DISH. Hopefully one TV source like the Hopper +, but a much better experience. I think all I will really lose is the "recent recordings" section on the Hopper + home page, which was a nice one-stop shop.
Was willing to be patient on the Hopper + as it had great potential, but it wasn't ready for prime time at launch, and now not ready for prime time almost 15 months later.