Zoom messes with my audio settings and my camera settings

[IKIPianoman]

I have been using zoom for 2 years teaching my music classes online and have not had any problems at all.   Recently when I get set up for a meeting I get everything set with my external audio mixer and my 2nd camera that I use to shine on my hands as I teach and everything is fine.   Then without warning zoom changes my 2nd camera to my first camera (the one on my computer) and also changes the mirror setting.   This is VERY annoying.  I have been very happy with zoom but zoom support has not helped much at all.   I updated zoom and my MacBook Pro but this is still happening.   Is anyone else having these kinds of problems?  How have you dealt with them?