While the bass levels when listening to streamed music are just fine, when I listen to a music DVD the Sub booms unpleasantly. When I go to the Sonos App to adjust the volume of the Sub, I don’t seem to be able to adjust it. The slider is not visible. The Sub is paired with an Arc and doesn’t show up separately in the App so I only seem to be able to adjust the overall volume of both. What am I missing?