Unhandled Exception: type 'Null' is not a subtype of type 'String'

[jazzyyoung]

Your environment.

• Version: ion-sdk-flutter v0.4.4, ion v1.9.0

What did you do?

Run ion-app-flutter

What happened?

Got this error after connected to room
E/flutter (16274): [ERROR:flutter/lib/ui/ui_dart_state.cc(186)] Unhandled Exception: type 'Null' is not a subtype of type 'String'
E/flutter (16274): #0 new RTCRtpTransceiverNative.fromMap (package:flutter_webrtc/src/native/rtc_rtp_transceiver_impl.dart:72:12)
E/flutter (16274): #1 RTCPeerConnectionNative.addTransceiver (package:flutter_webrtc/src/native/rtc_peerconnection_impl.dart:516:38)
E/flutter (16274):
E/flutter (16274): #2 LocalStream.publishTrack (package:flutter_ion/src/stream.dart:237:27)
E/flutter (16274):