mediasoup-ios-client: associated promise error

I again, When I try to handle the SendTransportListener events with a separate class I run into this error again:

[ERROR] transport_wrapper::+[TransportWrapper nativeProduce:listener:track:encodings:codecOptions:appData:]() | The associated promise has been destructed prior to the associated state becoming ready. The associated promise has been destructed prior to the associated state becoming ready.

when calling sendTransport.produce(...

the HandlerClass looks like:

class SendTransportHandler: NSObject, SendTransportListener {

    private let socket: Socket
    weak var delegate: SendTransportListener?

    init(socket: Socket) {
        self.socket = socket
        super.init()
    }

    func onProduce(_ transport: Transport!,
                   kind: String!,
                   rtpParameters: String!,
                   appData: String!,
                   callback: ((String?) -> Void)!) {
        l.info("** onProduce")
        guard let kind = kind else { return }
        let rtp = JSON(parseJSON: rtpParameters)
        let params: JSON = [
            "transportId": transport.getId() ?? "",
            "kind": kind,
            "rtpParameters": rtp
        ]
        guard let obj = params.dictionaryObject else { return }
        socket.request("produce", data: obj) { res in
            l.debug("xx produce result \(res)")
            callback(res["id"].stringValue)
        }
    }

    func onConnect(_ transport: Transport!, dtlsParameters: String!) {
        guard let params = JSON(parseJSON: dtlsParameters).dictionaryObject else { return }
        socket.syncRequest("connectProducerTransport", data: [ "dtlsParameters": params ])
    }

    func onConnectionStateChange(_ transport: Transport!, connectionState: String!) {
        l.verbose("** Send Con change: \(connectionState ?? "n/a")")
    }
}

// callsite

self.sendTransport = self.device.createSendTransport(sendTransportHandler.delegate,
                                                             id: id,
                                                             iceParameters: iceParams,
                                                             iceCandidates: iceCandidates,
                                                             dtlsParameters: dtlsParams)

This doesn’t happen if I just declare my RoomClient that’s already containing the sendTransport as SendTransportListener and handle the delegate methods there.

I see the associated promise error coming up a lot in other issues here. Wrapping in async queues didn’t really help. #67 might be related.