I should mention that,

- when targeting new mob, the chr will auto look back to the first mob, and if the first mob is out of range, he will do nothing, I have to get aggro or link to be able to cast shield lob on the new mob.
- If I waited for few seconds, I'll be able to use shield lob on the new target, seems like delay but it's not, I play different online game with no issue.
- I have not tried other spells or abilities to test
- I have a mac pro with the game installed on it, the shield lob works fine, I compared all settings, they are the same, I don't know where to look for this issue
- target lock is not active, i tried both options, nothing worked.