Mists of Pandaria I'm freezing in wow

[Xrod]

Good morning, this is to inform and at the same time to know if you can assist me.  My problem is the following, I downloaded the client from the website stormforge but every time I enter to play the character freezes for a few seconds and that's happening a lot I thought it was my Pc but I entered other servers and tried different games and not only happens with Stormforge Sheilun .

It is possible to play but it is very stressful and tedious because if you are a tank heal or dps and the game freezes for a few seconds you can die and it is very stressful.

I hope you can advise me to solve this problem.
 Thank you.