setting interpolate option as none, works better than interpolate and extrapolate

I have a game that the character inside it uses fixed velocity to move, but it makes it's movement kinda jumpy. I googled it and found that if i set the interpolate option in rigidbody as Interpolate or extrapolate, my problems would be fixed. but the situation actually becomes way worse. If set as "none", the character does this jumpiness once or twice every 2 seconds. but if i set it as the other two (both of them), the jumpiness becomes nonstop!

is there any other way to fix this behavior?