Does the iPod Touch 5g have a home button problem?

When I first got the iPod Touch 5g, the button seemed slightly sunken in and the more i used it, the button seemed to sink in a bit more. It worried me so i returned it and got a replacement. However the replacement did the same thing so i got a refund. It worried me cause i thought it would eventally sink in too much and stop working. I was thinking of giving the iPod touch 5g another chance but i want opinions first on the home button lol. Does yours seem slightly sunken in when you first got it? Did it sink in more after more use? Thanks 🙂