If that works, then it's possible it could have something to do with codecs selected during WebRTC negotiation vs. the hardware. Are able to compete calls successfully using other WebRTC apps like e.g. https://appear.in on this tablet?
Bug 1566584 Comment 6 Edit History
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If that works, then it's possible it could have something to do with codecs selected during WebRTC negotiation vs. the hardware. Are able to complete calls successfully using other WebRTC apps like e.g. https://appear.in on this tablet?