Sorry about that. I’ll take a look and see if I programmed something game-breakingly wrong. Is there any chance you weren’t holding down the jump key long enough?
I implemented a “jump-cancel” if you release the key before the jump’s apex.
I saw you posted your code on github so I took a quick look. I don't know if this is the cause or not, but could it be that the random offsets you're applying to the player position are affecting the jump? Only reason I think it might be related is because the jump does seem to go full height sometimes, so I could see the issue being tied to a random variable.