Sound Check not working with Dolby Atmos

I recently got an LG C1 TV with Dolby Atmos support. Atmos sounds amazing on the Apple TV, but (as designed) is much quieter than non-Atmos content, and not all songs support Atmos—leading to drastic volume differences in Apple Music. Apple’s solution to this is Sound Check, which is supposed to normalize the volume so that it won’t suddenly blare extremely loud non-Atmos content after playing an Atmos song. However, it doesn’t seem to be working for me. I have Sound Check on in the Apple TV settings, but there is still such an extreme difference in volume that it makes Atmos unusable. For Atmos songs I need to set the volume at about 90, while for non-Atmos songs I set it at about 30. Is this a known problem, and is there a solution?