Duty cycle of a square wave changing with tunable delay

This is a submodule. There is a clock associated with it however it happens earlier in the code so it just isn't shown. I was able to speak with my colleague yesterday and this is a problem he has run into before. What is happening is that the square wave coming in is not perfectly square meaning that there is a rise time and a fall time for each wave. furthermore the rise time and fall time are not the same so what happens is that as the waves are delayed an error builds up with each instance of the delay. He does know how to fix it, it would just take more time than what we have to do so.