Irelia R and E not working together when pressed at the same time, or near same time

On Irelia, if you try and perform her "Masquerade" combo (R and E at the same time so the E is masked by her ult), the E does not register quite often. I almost have to wait a second before casts and that defeats the purpose. If I cast E first then of course R will register. I've tried two different keyboards (Ducky and one I built on Glorious Master PC Race and it's the same issue). I've also posted on Reddit [https://www.reddit.com/r/IreliaMains/comments/b1j34x/issues_performing_the_masquerade/)] and it appears I'm not the only one who has this issue. Is this something that has already been discussed?

Jason