Hatred and Herald of Ash don't compute

I am using a level 76 duelist and run two auras: Hatred and Herald of Ash. Now when I brun both the skill button for Hatred (lower right of screen) tells me that it doesn't have enough mana to to run. The icon spins when activated, but has a dark center and a mouse over regeals "not enough mana". Each gem is carried on different armor.

In town: HoA 22% mana reserved in skill button tool tip. When I mouse over the gem itself it says 25% reserved. The reduced mana gem linked to HoA is now at x.74

For Hatred: skill button tool tip reads: 43% reserved; on gem, full 60%. The reduced mana gem linked to hatred is x.73.

My total mana is 636. When I leave Sarn and turn on my auras, this is what I get:

Hatred: 274 reserved 362 available
HoA: 140 reserved, 496 available

Both: 414 reserved, 222 available and Hatred center goes dark and "not enough mana" message appears.

Have no fear, they are both running.

The Hatred icon going dark just indicates that it doesn't have enough available mana to be turned on again.

Easy way to check, have a look at your tooltip DPS with hatred going, then turn on HoA. You'll see it buff again.

Well, "duh" on me.

Base dps: 18,305
Add Hatred: 22,553
Add HoA: 24,515

Thanks very much.

How or why would turn on an aura twice?

You can't. It's presumably just a coding artifact that it greys out. Might even be worth submitting a bug report for?

Thanks, I did a bug report.