Female Degu barking

We have bought 4 female degus and all was great untill today, one of the degus has started to try and mate with all the other's and then she sits and barks for ages. I thought only males barked. Is this right, help.xx

What does the "bark" sound like? Is it high-pitched or squeaky? Or low and growly?

I would double-check their sexes just in case but keep in mind that degus will mount each other even when not mating. It's usually a dominance or social thing.

It's a high pith barking?