Is the Sound normal that you hear when you push a game in or out? When you listen near to your ear it's feels like there is sand in it but it isn't :-) I don't know how to describe that sound... I was just wondering I own my 3ds for 3 days now and it's a new device.

I am afraid that if I am changing the games often they will scratch totally and won't work any more when the scratches go deeper...
Is it normal that the 3ds sometimes does not reads the game and I have to put it out an in again. It happens 1 times in 30

My 3ds does that sand-like sound too. I've had it for 2.5 years and my games still work just fine.

Thank you for your answer! :-)

Did you change games often? I think Mario Kart 7 and Smash Broth are such games that are going to be change very often.