Problem of sound with Zoom

Hello, 

I have a problem of sound with Zoom with my new MAC Ventura 13.6.1.

I want to give my singing class, and when I play the extern piano, my student doesn't hear any sound, but he can hear my voice. I already check the parameters, and put the origin sound for musicians. But it doesn't still work.

It's works with other applications like Teams and Meet, but not with Zoom. It seems to be a software incompatibility with  Zoom. How could I fix it please ?

Thank you