My new 3ds buttons are not very clicky, can I do something to fix them?

Hello, I am having trouble with my new 3ds (not the xl). I got it a few weeks ago, and I am noticing my start/select buttons feel weird.

When I press the start button, it feels stiff and hard to press, but after one press it feels normal. But when I press it again just a few seconds later, it becomes stiff again.

But sometimes what I just happens to the other button and the other button starts working fine?

Just this morning, however, the start button has been slightly mushy, and the select button is the one with the stiffness problem.

I contacted the seller and they suggested that it might be dirt under these buttons. But is there any way to get it out without taking apart the console? Or is it another problem causing these buttons to behave this way? Thank you.