We've lived in our apartment for a little over 3 years now. Since the day we moved in,
The outlets in our kitchen and bathroom has made a loud popping sound every couple of
Minutes or so. What could it be?

THREE YEARS??
And in all that time you never thought of calling the landlord/super/whatever? You never thought it might be something bad, considering it's electrical?

It doesn't matter what the noise is, they should fix it!

I forgot to say in my question, that I did call the landlord. He sent a repair guy
Over. The repair guy said nothing was wrong, that "the sound let's you know
It's on".

The sound is letting you know there could be a serious issue. Outlets and switches do not making any noise when oerating properly.

Insist that the landlord get an qualified licensed electrician to check this out ASAP, and not just a "repair guy".

The repair guy said nothing was wrong, that "the sound let's you know
It's on".Wow. If this was not such an unbelievably stupid statement (on his part) it would be funny. Lol :p

I agree Stan. Scary how some "experts" make crap up.

So does that mean because my outlets are not making noise that mine are not on?