Playing Music w/Siri vs. with Music App

It seems to me that if you play music using Siri voice commands, then some features available in the regular Music app don't work. For example. when asking Siri to shuffle "Blues," tracks that are marked "Skip When Shuffling" will play as part of that mix. But shuffling the genre directly from the Music app skips those tracks.

Also, it seems that playing music with Siri doesn't engage "Sound Check." Volume levels seem inconsistent.

I love playing music with voice commands, but does anyone know why these features don't work when Siri plays your music, but do work in the Music app?