Ok couple of suggestions first try a non invasive way to clean out the contacts most of the time dirt and grime eventually build up and make buttons non responsive there is some good tutorials on youtube now if cleaning doesn't work you can usually buy replacement parts from places like Deal Extreme just be aware it will require some soldering as well as needing a tri-wing screw driver and there are tutorials for that as well on youtube but my suggestion try to clean first its cheaper and less scary I opened mine took everything apart and took me a month to put it back together again before I looked on youtube for tutorials so I start there first watch them several times and make sure you are comfortable in your abilities before you start that project