Forearm really hurts - bicep curl

[JBEXT81]

Hey guys,

When i curl using a barbell my forearms hurt like hell regardless of how hard or how wide i grip the bar!!!! The pain is in the top of my forearm and gets worse as i rech the peak of my contraction and also gets worse as i increase the weight.

When i do the same weight on a cable pulley it doesn't hurt at all to nearly zill - anybody else have this or know how to remedy this????

thanks