Hi!
Make sure you have the exact right model replaced for the Button Circuit Membrane. If this is the case, please clean the motherboard (the pins that will push against the button circuit membrane) cleaned with isopropyl alcohol. Otherwise, replace it again and see if that works.
If all of above failed, replace the rubbers as well to see if that makes a difference. Otherwise it is something on the motherboard (but this most of time not the case.