About two years ago, I was adding onto my system. I was having trouble with a M1KPAS enrolling into the system. I wasn’t able to assign it to the keypad address I wanted (would revert to address 6 by itself) and then would become unresponsive. It ended up being a bad keypad out of the box. Luckily, the retailer I purchased it through was really helpful and I was able to swap it out, but it did make for a very confusing weekend trying to get the keypad to enroll into the system.