Opentok webrtc error - A constrain specified is not supported by the browser (getUserMedia error: NotSupportedError)

[mhamester]

I get the above error using the Opentok basic chat JS code.
I get the error on session connect.
I get the error on Android Firefox and Iphone Safari.
I am using the below Opentok lib in my Index.html
<script src="https://static.opentok.com/v2/js/opentok.min.js"></script>

My sessions work correctly in Edge, and Chrome and Firefox on Win10.

I am a paying subscriber to Opentok.

Thanks,

Mark