Is it normal for a pot bellied pig to "koink"?

My neighbor has a pot bellied pig, and it makes some of the strangest sounds I've head.

It doesn't normally oink: It koinks. [KOY-unk] Try to sound it out that's the closest I can get to explaining it.

Sometimes it wakes me up at 3am, and when I look at it out the window, it's staring at me.