There might be moisture in between the keypad membrane and the circuit board of the remote. It could have been through spilling water on the remote or fluid from a leaky battery. If you're handy you can try taking apart the remote. Remotes are commonly held together by one or two screws and then clips around the perimeter. You can pry it open after taking out the screws. In my case I actually wash the circuit board and the keypad membrane with soap and running water and then put it back together again after drying out.