Help! My OBS always goes super laggy when trying to play media, especially stinger transitions!

[SSBC]

Please, someone help! I've spent at least the past hour trying to fix this issue that whenever I have a stinger animation play, the whole OBS render lags to like 5-10 fps, I'm assuming. And just in general, OBS feels like it is limited even though I know my computer can handle it and cpu only runs 30%. I'd like to use more potential the cpu usage or find a way to make this less laggy. By the way, this occurs even when not streaming! It is terrible. If you are able to help me out, please reach out! I'd quickly supply things you need to help me solve this. Thank you!