Haste effects stacking?

[Not A Taco]

I have a small army of rares clumped together with two having hasted aura. I can't roll or run fast enough before even the white mobs in the pack are hitting me multiple times and almost instantly on top of my next position. Even with cast speed I can't get enough time to get more than one aoe off and the chill/knock back/slow on it is doing nothing.

[GeforceJoe]

Invest in defense?