I tried syncing it up with 120 fps instead, since it will be easier to compare to 60 and 30 fps.
DesiredFrameTime is now at 0.08334,. which means that mult# is at 1. When I then set it to 60 fps, the frametime sets to 0.016667 and mult# is being set to 2.
I'm applying the current position of the player's current position + or - a set speed which is set differently so I can have momentum and stuff. Everything is set with floats
I think there's something else weird with my code, so I'll have to look more into it. Thanks for the help anyway!
Edit:
So, after just testing around, it seems to be something with how I calculate my gravity... How I do it now is that I have a vsp (vertical speed) value that controls how much Y is going to be changed. When you jump, it's being set to a set value and decreased by a set value all the time. The jump value and gravity is affected by the mult# value. Should I do this differently?