Crappy sound Cubase elements 8

Hi. have an issue with bad sound drivers on my mac. Cant find the right spot for changing audio drivers. One one occasion there pop up a question on choosing drivers ( see photo) then everything was ok. But now I’m back to dreadful sounds again, and can’t fint the spot for choosing right. Anyone??
Mac os sierra. Cubase elements 8.

Manual -> setting up your system -> setting up audio