Importing video with Media Express (3.5.3)

I have an Intensity Shuttle connected to a MacBook Pro via USB3.
When I view a video before importing it or importing it, I can not hear the clip sound track.
The sound is very useful to choose cuts in and out.

What to do to hear the sound during these phases of work.

Thank you for your help

Go into Sound Preferences and check which audio output has been selected.