I finally have a good configuration for the media volume, I.e. the one that matters most of the time. In the engineering menu audio section -> loudspeaker mode -> media I’ve set level 0 to 160, then added 6 per step so that level 1 is 166, level 2 is 172, etc.. That gives an almost off level for the lowest volume and an almost loudest level for the highest volume.
It was a very awkward adjustment. Starting slightly higher than 160 caused all levels to be way too loud, and much lower than 160 meant that all volume levels were way too quiet. That setting is definitely not linear across the whole range!
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