Unable to access microphone in chrome browser when loading jitsi meet in iframe

I have installed Jitsi meet in Ubuntu server and loading the meet in iframe.
I’m getting error “Unable to access to microphone”.
My Chrome Version 75.0.3770.100

Browser error logs
Logger.js:125 [modules/connectivity/ParticipantConnectionStatus.js] <e.value>: No participant for id: c78c3d4f
Logger.js:125 [JitsiConference.js] <e.sendMessage>: Failed to send a ping request or response.

@damencho can you please help me in this issue.
Thanks in advance.

Check https://jitsi.org/qi#advanced-configuration

Thanks @damencho, I have configured the ICE settings.
Video conference used to work earlier. But suddenly stopped working today.

These are the version details.

dpkg -l | grep -i jitsi

ii jicofo 1.0-451-1 amd64 JItsi Meet COnference FOcus
ii jitsi-meet 1.0.3508-1 all WebRTC JavaScript video conferences
ii jitsi-meet-prosody 1.0.3186-1 all Prosody configuration for Jitsi Meet
ii jitsi-meet-web 1.0.3186-1 all WebRTC JavaScript video conferences
ii jitsi-meet-web-config 1.0.3186-1 all Configuration for web serving of Jitsi Meet
ii jitsi-videobridge 1104-1 amd64 WebRTC compatible Selective Forwarding Unit (SFU)