Hello,
I have been recording my first course and uploading course videos as soon as I finish them.
The problem I'm facing is, even though my original videos are having good audio quality, the quality is lost after uploading them to Udemy. When I click on Preview option and try to view the video, I found that the quality of the audio is not satisfactory (at least to me). I'm worried that students also raise this concern and leave poor reviews on my course.
I'm using Boya BY-M1 mic and the recording quality of original video is almost as good as other instructors at Udemy. After uploading the videos it is a completely different story. 
You can compare my original audio quality with final video compressed to 720p at Udemy side. I attached both of them.
I'm very frustrated with the final video's audio quality. Please help.
FYI: I'm using QuickTime Player in MacbookPro to record both Audio and Video.