My registered users (by default "Suscribers") can't vote

Hello,

My registered users (by default "Suscribers") can't vote to the questions. They also can't report. Only the Admin can do it.

My site is a wordpress simple instalation.
I have assigned the capabilities for users in the Q&A Settings and tried giving Suscribers the same capabilities as Administrator, but it doesn't work.

I deactivated all my plugins, but the problem persist.

My Wordpress is 3.6.1

How to fix this?

Thank you,
Isabel