Umm, it's called Always Randomize Contents. As you mentioned at the top of your post.

It doesn't work on the next level down. It works on the list you set it for, and not any further (ie. the items in the list, not the items in any sublists). So you have to set it for every list whose contents you want to be selected at random. So try it for the actual list that contains songs (Bleach for instance).

Of course now there will be no way not to play them at random by selecting the playlist.

Bruno