I think it's the fact the pronunciation is done by a language software program. It puts vowels together to pronounce the words, and doesn't always give the right sound. I'm fluent in German (living 5 minutes from the border) and sometimes I don't even understand half the things said in German because of this. I imagine it's the same in French.
It is a voiced uvular fricative /ʁ/. You can listen to it here: https://en.wikipedia.org/wiki/Voiced_uvular_fricative