Combine axis doesn't update properly when input axis are moved quickly

[EkajArmstro]

A video example of what I'm talking about: https://www.youtube.com/watch?v=DpcMT_30eVA

I'm trying to combine to racing pedals into a rudder axis. If I move the left pedal slowly then it works as expected and the output axis goes from 50->0->50. If I move the left pedal quickly then the combined axis gets "stuck" to the left of 50 until I move the left pedal again. When in this state, if I move the right pedal, I can never fully get to 100 because I'm adding 50 to less than 50.