Nostalrius Begins - Quality wow vanilla realm (1.12)

I finally got this running and it works pretty damn good, apart from one problem. When i use some skills, mainly seems to be pet skills. Sweetfx seems to be turning off and on. No idea why since i am not even pushing a key, but i am using the mouse for the skills.

Does anyone know how to fix it or why it's even doing this. Would really appreciate any help. Thanks.