Is my precious Gameboy original faulty?

Recently I decided to relive my days of yore by getting an old gameboy original (nice and cheap) and Pokemon Blue. The first unit I received was scratched to [four letter expletive] and had a really odd sound coming out of the speaker; a kind of loud buzzing and a high-pitched squeal combined. I returned it for a new one. To my horror, my new unscratched model makes EXACTLY the same sound. They're totally identical, even the volume of the buzz is the same. I tried changing my batteries and everything, but still the squeal cometh.

So did the gameboy always make such a god-awful sound, or am I just unlucky? I'm assuming the former is correct, but I just want confirmation.

The only sort of squealing or buzzing I've ever heard is the interference that happens if my cell phone is right next to my Gameboy. But the handheld itself shouldn't be making any extra noise on its own. I'd take it to the store where you bought it and demonstrate it for them. If it's something normal, they'll tell you. If not, they'll get you another exchange ;) Best of luck!