Is it normal for a guinea pig to chatter their teeth for no reason?

[adobo]

I'm sure there's a reason, but by "no reason" I mean like they are just resting, and all of a sudden they chatter their teeth. Is this normal?

 

[Piggies&buns]

Yes it’s normal but why your piggy is doing it on that particular occasion would be speculation.

There is also a different type of chatter which is scissoring - sharpening sound. It’s a slightly different noise from chattering.

 

[Julie M]

Sometimes i just have to look at my grumpy Chip the wrong way and he chatters. Lol