Sending mail via smtp over ssl produces error message

[RFL]

Hi there
I am sucessfully using the Simple Smtp SSL code with QT5. It works great, the email goes through and everything seems fine, but I get the following error message:
qt.network.ssl: QSslSocket::startClientEncryption: cannot start handshake on non-plain connection

When I check, if the socket ist encrypted socket->isEncrypted() it gives a positive result.
Does this seem familiar to anyone or am I chasing ghosts unnecessarily?
Is it because we open the socket already encrypted and then the command socket->startClientEncryption() is superfluous?

Thank you all in advance!

// TERMINAL
Init STATE ------------------------------
readyRead
Server response code: "250"
Server response:  "250-smtp.mailserver.com\r\n250-SIZE 75000000\r\n250-AUTH PLAIN LOGIN\r\n250-AUTH=PLAIN LOGIN\r\n250 ENHANCEDSTATUSCODES\r\n"
Handshake STATE --------------------------
qt.network.ssl: QSslSocket::startClientEncryption: cannot start handshake on non-plain connection
is encrypted 1? ::  true
"Unknown Error"
is encrypted 2? ::  true
readyRead
Server response code: "250"
Server response:  "250-smtp.mailserver.com\r\n250-SIZE 75000000\r\n250-AUTH PLAIN LOGIN\r\n250-AUTH=PLAIN LOGIN\r\n250 ENHANCEDSTATUSCODES\r\n"

// C++
void Smtp::sendMail(){
...
 this->from = from;
    rcpt = to;
    state = Init;
    // ---- Change for SSL ---------------------------------------
    socket->connectToHostEncrypted(host, port);
...
}

void Smtp::readyRead(){
...
    else if (state == HandShake && responseLine == "250")
    {
        qDebug() << "Handshake STATE --------------------------\r";
        qDebug() << "is encrypted 1? :: " << socket->isEncrypted();
        socket->startClientEncryption();       

        if(!socket->waitForEncrypted(timeout))
        {
            qDebug() << socket->errorString();
            state = Close;
        }
        //Send EHLO once again but now encrypted
        *t << "EHLO localhost" << "\r\n";
        t->flush();

        state = Auth;
        qDebug() << "is encrypted 2? :: " << socket->isEncrypted();
    }