I have had my 3ds for a little over a year (I have the extended warranty) and for a while the R button has been a little sticky. But now, the L button has suddenly stopped working without any warning signs. There was no stick to it, it feels and clicks fine.. Any help with this? Is this problem common??
This happened to my friend's 3DS. L buttons just tend to break a little too easy. You just need to send it into Nintnento for repair, and if you still have your warranty I'm pretty sure they'll fix it for free because the L button malfuctioning is a Software Problem and not accidental hardware issue. So they cover it.
If you haven't done anything yet, try placing your mouth over the entire button and sucking in as hard as you can. What would often happen with the Nintendo DSi is that dust would get within the buttons. Placing your mouth and blowing in would work too, HOWEVER that may cause condensation to enter your system and destroy it. That is a small possiblility, if you wish to take the risk. Sucking doesn't work quite as well, but it does work. Give it a try!