m_critical_mutex.lock();
    debug() << "Sending track... " << bundle.url().path().utf8() << endl;
    int ret = LIBMTP_Send_Track_From_File(
        m_device, bundle.url().path().utf8(), trackmeta,
        progressCallback, this, parent_id  // callbacks only in libmtp >= 0.0.15
    );
    m_critical_mutex.unlock();

    if( ret < 0 )
    {
        debug() << "Could not write file " << ret << endl;
        Amarok::StatusBar::instance()->shortLongMessage(
            genericError,
            i18n( "File write failed" ),
            KDE::StatusBar::Error
        );
        return 0;
    }