Bug 212367

Steps to reproduce: 

1. On iPad/iPhone, go to https://webrtc.github.io/samples/src/content/devices/multi/.
2. Allow to use mic/camera, then you can see yourself and hear your sound from the left-handed "getUserMedia()" video tile. 
3. Connect iPad/iPhone to safari for local debugging, access the console of iPad/iPhone safari on this page.
4. Getting the left-handed "getUserMedia()" video DOM by   let leftVideo = $('video'); then leftVideo.load();
5. If you execute leftVideo.load(); 7-8 times, especially execute it quickly, then you can't hear yourself. When you can't hear yourself, doing leftVideo.load(); one more time will fix the audio. Then it will become "no audio" -> "can hear" as you execute load() method.


This issue can be found on iPad(7th generation) with iPadOS 13.2.2 and iPhone 6S with ios 13.4.1. But I can't reproduce it on my MacOS so far. 


This is affecting our web app using webRTC to establish calls between users. Our users using iPad to iPad or iPad to iPhone have reported sometime they can't hear other user during the cal. After investigation, we found that in the code we use load() method to reload the <video> when audio track or video track is changed, it will cause audio not being played randomly after load() is being called.