I can't hear anything that the othe person is speaking but they can

[Schneider1]

I can't hear what the other person is saying but they can clear as day. I have turned on the volume to max, I have connected the voice audio, and checked the little speaker at the corner, but nothing works.

How do I fix it? 

[LonnieZ]

Zoom on my mac goes through periods where it freezes and says "internet unstable" and I can't hear anyone on the other end that then it connects again and keeps doing that on/off connection.  Meanwhile I have high bandwidth, my computer indicates I have good wifi connection, and a PC near me has good wifi connection.  What is the issue with zoom and Macs?  this problem comes in waves.  Sometimes zoom is great and sometimes it cuts in and out frequently.  How do I fix this?