Nostalrius Begins - Quality wow vanilla realm (1.12)

Hello everyone, 2 weeks ago I noticed I would stutter for a split second every time I got a critical hit. I tried disabling all addons, reinstalling the client, enabling/disabling vsync, and it still happens. I didn't change anything, and I don't remember installing a new addon when it started. My internet is also fine, there's no uploading or downloading.

My specs are Intel i7 cpu, Ati R9 290 gpu, 6gb ram, and ssd storage drive. Are there any other tweaks I can try doing in the options to see if it changes anything? It only happens the moment I get a critical hit. Any help is appreciated, thanks.