it's seems that physic broke on certain linux version. Can you tell what is your hardware and if it happen everytime you'r jumping ? I didn't have time to check the issue but I will try to fix it if I can reproduce it :P
I re-export the project on windows and the issue seems to be fix... maybe an export problem. I will do the same for the linux and mac version but I can't test them for the moment. Tell me if it's better now. Thanks.