Hey guys, I noticed that when I push down on the speaker of the rmbp (late 2013) I hear very very light "cracking sound". It is not the "click click" sound that some people are experiencing. It is as if there are some gaps between the metal. I am worried about this because a hole on the speaker grill is not drilled completely, there is a tiny bit of metal stuck in the hole. Is this normal? please help.