Flash player not working with webcam

Hello.  When I try to use either my built-in iSight camera or an external Logitech camera, the Flash player settings window opens and then locks up.  The only thing I can do is close the window out.  I'm pretty certain this began with the most recent Flash player update.  No error messages or crash reports (that I'm aware of).  The same thing occurs whether I try it in Firefox, Opera or Safari.

Has anyone else had an issue like this?

I'm using an iMac 5k Retina (27") OS X Yosemite with 24GB memory, 3.5 Ghz Intel Core i5 processor and AMD Radeon R9 M290X 2048MB graphics.

Thanks.

Marty