I figured it out. Using tv remote push Home icon. Scroll left to settings icon and a Quick Settings menu should pop up above without clicking. Go up and scroll to Audio Input and switch to proper input/ output.
I have the same issue
This solution did not work for my Samsung TV. The volume sticks, it can no longer connect to the internet, and now the mute icon keeps flashing. I do have have a Bose Sundance attached via HDMI.