Playbin3 audio description

playbin3 in python3 Gtk with Gst.ElementFactory

The audio stream with audio description is always automatically selected.
Is there a flag to prevent that?
I am currently using the flag 0x13 so that no subtitles are displayed.

import gi
gi.require_version('Gtk', '3.0')
gi.require_version('Gdk', '3.0')
gi.require_version('Gst', '1.0')
gi.require_version('GstVideo', '1.0')
from gi.repository import Gst, GObject, Gtk, Gdk
from gi.repository import GstVideo
import warnings

warnings.simplefilter("ignore")

channel_url = "https://mdrtvthhls.akamaized.net/hls/live/2016880/mdrtvth/master.m3u8"
    

class MainWin(object):
    def __init__(self):
        
        self.is_playing = False
        self.tv_icon = "video-display"
        self.window = Gtk.Window()
        self.window.set_icon_name("video-display")
        self.window.set_keep_above(True)
        self.window.set_title("TV-Player")
        self.window.resize(427, 240)
        screen = Gdk.Screen.get_default()
        monitor = Gdk.Screen.get_primary_monitor(screen)
        monitor_n_geo = screen.get_monitor_geometry(monitor)
        print(f"Monitor Resolution: {monitor_n_geo.width}x{monitor_n_geo.height}")
        self.window.move(monitor_n_geo.width - 427, monitor_n_geo.height - 240)
        self.window.connect("destroy", Gtk.main_quit, "WM destroy")
        
        vbox = Gtk.VBox()
        self.window.add(vbox)
        
        self.movie_window = Gtk.DrawingArea()
        vbox.add(self.movie_window)
        self.window.show_all()

        self.player = Gst.ElementFactory.make("playbin3", "player")
        self.player.set_property("flags", 0x13) # to prevent subtitle
        self.player.set_property("volume", 1.0)
        bus = self.player.get_bus()
        bus.add_signal_watch()
        bus.enable_sync_message_emission()
        bus.connect("message", self.on_message)
        bus.connect("sync-message::element", self.on_sync_message)
        
        self.window.connect('delete-event', self.on_close)
        self.window.connect("key-press-event",self.on_key_press_event)
        self.window.connect("window-state-event", self.on_window_state_event)
        
        self.player.set_state(Gst.State.NULL)
        self.player.set_property("uri", channel_url)
        self.player.set_state(Gst.State.PLAYING)
        self.window.set_title("MDR")
        self.is_playing = True
        
        
    def fullscreen_mode(self):
        if self.__is_fullscreen:
            self.window.unfullscreen()

        else:
            self.window.fullscreen()
        
    def on_key_press_event(self, widget, event):
        key = Gdk.keyval_name(event.keyval)
        if key == "q":
            self.player.set_state(Gst.State.NULL)
            print("player stopped")
            self.window.destroy()
        if key == "f":
            self.fullscreen_mode()
        if key == "1":
            self.playTV(None, 0)
        if key == "space":
            self.pauseTV()
        if key == "m":
            if self.player.get_property("mute") == False:
                self.player.set_property("mute", True)
                print("audio muted")
            else:
                self.player.set_property("mute", False)
                print("audio unmuted")
        if key == "Down":
            v = self.player.get_property("volume")
            self.player.set_property("volume", v - 0.1)
            print(f"Volume: {v:.2f}")
        if key == "Up":
            v = self.player.get_property("volume")
            self.player.set_property("volume", v + 0.1)
            print(f"Volume: {v:.2f}")
            
    def pauseTV(self, *args):
        if self.is_playing:
            self.player.set_state(Gst.State.PAUSED)
            self.is_playing = False
        else:
            self.player.set_state(Gst.State.PLAYING)
            self.is_playing = True            
        
    def on_close(self, event, *args):
        self.player.set_state(Gst.State.NULL)
        print("player stopped")
        self.window.destroy()

    def on_message(self, bus, message):
        t = message.type
        if t == Gst.MessageType.EOS:
            self.player.set_state(Gst.State.NULL)
        elif t == Gst.MessageType.ERROR:
            self.player.set_state(Gst.State.NULL)
            err, debug = message.parse_error()
            print ("Error: %s" % err, debug)

    def on_sync_message(self, bus, message):
        if message.get_structure().get_name() == 'prepare-window-handle':
            imagesink = message.src
            imagesink.set_property("force-aspect-ratio", True)
            imagesink.set_window_handle(self.movie_window.get_property('window').get_xid())
            
    def on_window_state_event(self, widget, ev):
        self.__is_fullscreen = bool(ev.new_window_state & Gdk.WindowState.FULLSCREEN)

Gdk.threads_init()
GObject.threads_init()
Gst.init(None)        
MainWin()
Gtk.main()

The content of the m3u8

#EXTM3U
#EXT-X-VERSION:4
#EXT-X-INDEPENDENT-SEGMENTS
#EXT-X-STREAM-INF:BANDWIDTH=1672000,AVERAGE-BANDWIDTH=1460800,CODECS="avc1.4d401f,mp4a.40.2",RESOLUTION=640x360,FRAME-RATE=50.000,AUDIO="program_audio",SUBTITLES="subs"
master_640x360.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=6520800,AVERAGE-BANDWIDTH=5640800,CODECS="avc1.64002a,mp4a.40.2",RESOLUTION=1920x1080,FRAME-RATE=50.000,AUDIO="program_audio",SUBTITLES="subs"
master_1920x1080.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=4224000,AVERAGE-BANDWIDTH=3660800,CODECS="avc1.640020,mp4a.40.2",RESOLUTION=1280x720,FRAME-RATE=50.000,AUDIO="program_audio",SUBTITLES="subs"
master_1280x720.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=2182400,AVERAGE-BANDWIDTH=1900800,CODECS="avc1.4d401f,mp4a.40.2",RESOLUTION=960x540,FRAME-RATE=50.000,AUDIO="program_audio",SUBTITLES="subs"
master_960x540.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=1034000,AVERAGE-BANDWIDTH=910800,CODECS="avc1.4d401e,mp4a.40.2",RESOLUTION=480x270,FRAME-RATE=50.000,AUDIO="program_audio",SUBTITLES="subs"
master_480x270.m3u8
#EXT-X-MEDIA:TYPE=SUBTITLES,NAME="Untertitel",DEFAULT=YES,AUTOSELECT=YES,FORCED=NO,LANGUAGE="de",GROUP-ID="subs",URI="master_cc.m3u8"
#EXT-X-MEDIA:TYPE=AUDIO,LANGUAGE="de",NAME="Deutsch",AUTOSELECT=YES,DEFAULT=YES,GROUP-ID="program_audio",URI="master_audio1.m3u8"
#EXT-X-MEDIA:TYPE=AUDIO,LANGUAGE="de",NAME="klare Sprache",AUTOSELECT=YES,DEFAULT=NO,GROUP-ID="program_audio",URI="master_audio2.m3u8"
#EXT-X-MEDIA:TYPE=AUDIO,LANGUAGE="de",NAME="Audiodescription",AUTOSELECT=YES,DEFAULT=NO,GROUP-ID="program_audio",URI="master_audio3.m3u8"