No musescore audio on new mac

I had Musescore on my old macBook and enjoyed using it a lot. Unfortunately my mac had an accident and was smashed and I had to get a new one.

I downloaded Musescore 2.1 on my new MacBook 12", macOS High Sierra, Version 10.13.1, and experience now that the sound does not work.

My friend also has the same problem. His mac is a MacBook Air 13”, OS X El Capitan, Version 10.11.6

I am very disappointed about this, since it seriously affects my music work, and I wonder what to do...