
I eventually was able to go up to 100 volume from my usual 12 and still hardly hear anything.

It also continues to gradually lower if I try to ignore it and pump the audio up. This means I have to do this three or four times during movies. I must power off the TV and bring it back up to fix the audio.

If I switch to another HDMI device or Roku app the issue continues. This happens over both my HDMI ARC soundbar and my 3.5mm headphones plugged directly in to the TV.

The volume numbers do not change, the audio just suddenly drops very low. For the last two weeks the audio on my Roku TCL 65R615 has been suddenly dropping very low after about 40 minutes of using any app on my Nvidia Shield Pro (HBOMax, Plex, YouTube, SOundTV).
