Right-click the pic you see in testmycam.
Then click Settings.
Go to the fourth tab for Camera.
See if Integrated Camera is selected. If not, select this option. Refer to this page: http://helpx.adobe.com/flash-player/kb/troubleshoot-games-video-audio- flash.html#main_Webcam
(It's for Mac; but will help you to locate the option.)
Also, please let us know what you see in the second box of the following page: http://helpx.adobe.com/flash-player/kb/find-version-flash-player.html
This sounds like a reported bug against certain webcams and the latest version of Flash Player. When you have a minute, could you vote for the following bug?