Mana Reserved on Aura Bug?

Hello,

I am running an RF incinerate build. Long story short, he is currently rocking two auras: Purity of Fire and Vitality. Both are supposed to reserve 35% of mana, and if I look at the gem, that is what is says. However, when I look at the skill on the action bar, it says 40%. I am using Alpha Howl, so it should be less than 35%, not more! If I do the math on my mana bar it is indeed reserving 40% for each of those auras. Does anyone know what is up with that?

Are the auras linked to any support gems, or are they socketed in an item with a "Socketed gems are supported by a level X [Support Gem]" mod?

Ah that must be it. Interesting that the mana multiplier affects auras, but i guess that makes sense. Thank you stranger! I was so confused there for a while.