Flute sounds really low compared to tutorial video

Watching & following the steps in “Introduction to Dorico for Finale Users”, initially I had no sound from Dorico 5. Re-installed Dorico once, installed FlexAsio mentioned in the previous forum, still no luck.
After the second re-installation, it started to make sounds, no idea of the cause. But the trouble now is the Flute sound is too low to be heard (sounds fine in the tutorial video), while the Yamaha piano is at a fine audible volume. How do you make it work like the tutorial video?
(It took me a few hours to get here.)
Thank you.

Solved: After the third(!) re-installation, and third time recreating brand new project file (following the tutorial video), it is finally working as expected.
I hope this post helps some other unlucky like myself.