iOS - TwilioVideo - Unable to connect on call with remote participant - ios

Question

I am developing app with video calling functionality and I am using Twilio Video for that.
Currently using TwilioVideo SDK v4.6.2 and iOS Version 14.x and Above
I am not able to connect to the TwilioVideo room
Below is my code:
func connect() {
guard let accessToken = self.accessToken, let roomName = self.roomName else {
return
}
prepareAudio()
prepareCamera()
let connectOptions = ConnectOptions(token: accessToken) { (builder) in
builder.isDominantSpeakerEnabled = true
builder.isNetworkQualityEnabled = true
if let localAudioTrack = self.localAudioTrack {
builder.audioTracks = [localAudioTrack]
}
if let localVideoTrack = self.localVideoTrack {
builder.videoTracks = [localVideoTrack]
}
if let preferredAudioCodec = TwiloVideoSettingsManager.shared.audioCodec {
builder.preferredAudioCodecs = [preferredAudioCodec]
}
if let preferredVideoCodec = TwiloVideoSettingsManager.shared.videoCodec {
builder.preferredVideoCodecs = [preferredVideoCodec]
}
if let encodingParameters = TwiloVideoSettingsManager.shared.getEncodingParameters() {
builder.encodingParameters = encodingParameters
}
builder.region = "gll"
builder.roomName = roomName
}
self.room = TwilioVideoSDK.connect(options: connectOptions, delegate: self)
UIApplication.shared.isIdleTimerDisabled = true
}
Response in not received from Twilio in either of the methods mentioned below
func didConnect(to room: Room) {
NSLog("Room: \(room.name) SID: \(room.sid)")
if (room.remoteParticipants.count > 0) {
self.remoteParticipant = room.remoteParticipants[0]
self.remoteParticipant.delegate = self
}
self.delegate.videoServiceManagerDidConnectToRoom(name:room.name)
}
func roomDidFailToConnect(room: Room, error: Error) {
NSLog("Failed to connect to a Room: \(error).")
self.delegate.videoServiceManagerFailToConnectRoom(error: error.localizedDescription)
self.leaveRoom()
}
I am not able connect to the room every time and sometimes I get the error mentioned below :
Failed to connect to a Room: Error Domain=com.twilio.video Code=53000 "Signaling connection error" UserInfo={NSLocalizedDescription=Signaling connection error, NSLocalizedFailureReason=SIP error 408}.
When I check the Twilio logs in debug mode I am not getting any error.
Please guide me to rectify if there is any mistake in my code

Answer 1

Twilio employee here. Error 53000 is somewhat vague and could occur due to different things: https://www.twilio.com/docs/api/errors/53000
I'd suggest the following next steps:
try reproducing this error using the iOS Quickstart app (https://github.com/twilio/video-quickstart-ios)
try running our Networktest on the problematic device: https://www.networktest.twilio.com