Story: I let some kid play my 3ds xl and he smashed the buttons with his fingers. Thought the 3ds xl was stable enough to handle it. After I got my 3ds xl back, the y and b buttons are less clicky than the A and X.
Let me try to explain. When you press down on a happy healthy button, you don't feel like you're touching the 3ds xl itself. You feel a wonderful small gap between those two. Now when you press the smashed button, it feels like your thumb is actually touching the 3ds xl. No gap. Clicking feeling has lessen.
It might sound stupid but i'm extremely ocd when it comes to this and i'll personally stop using my 3ds xl for 6 weeks just for the 3ds to have the buttons fixed. Also some shell scratches 
I don't know if I'm under warrenty, I bought this at Feburary and I registered it under club nintendo. So ****, wut should I DO 
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Also, I understand Nintendo has 12 month warrenty..? If i'm not mistaken.