diff --git a/.gitignore b/.gitignore
index eec472f..cb14cfd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+.DS_Store
 # Byte-compiled / optimized / DLL files
 __pycache__/
 *.py[cod]
diff --git a/tubesync/sync/models.py b/tubesync/sync/models.py
index 35fcda1..fb4d950 100644
--- a/tubesync/sync/models.py
+++ b/tubesync/sync/models.py
@@ -103,7 +103,8 @@ class Source(models.Model):
     EXTENSION_M4A = 'm4a'
     EXTENSION_OGG = 'ogg'
     EXTENSION_MKV = 'mkv'
-    EXTENSIONS = (EXTENSION_M4A, EXTENSION_OGG, EXTENSION_MKV)
+    EXTENSION_MP4 = 'mp4'
+    EXTENSIONS = (EXTENSION_M4A, EXTENSION_OGG, EXTENSION_MKV, EXTENSION_MP4)
 
 
     # as stolen from: https://wiki.sponsor.ajay.app/w/Types / https://github.com/yt-dlp/yt-dlp/blob/master/yt_dlp/postprocessor/sponsorblock.py
@@ -398,7 +399,7 @@ class Source(models.Model):
             else:
                 raise ValueError('Unable to choose audio extension, uknown acodec')
         else:
-            return self.EXTENSION_MKV
+            return self.EXTENSION_MP4
 
     @classmethod
     def create_url(obj, source_type, key):
diff --git a/tubesync/sync/youtube.py b/tubesync/sync/youtube.py
index 00ae958..a55e92a 100644
--- a/tubesync/sync/youtube.py
+++ b/tubesync/sync/youtube.py
@@ -73,6 +73,10 @@ def download_media(url, media_format, extension, output_file, info_json,
 
     def hook(event):
         filename = os.path.basename(event['filename'])
+    
+        if event.get('downloaded_bytes') is None or event.get('total_bytes') is None:
+            return None
+
         if event['status'] == 'error':
             log.error(f'[youtube-dl] error occured downloading: {filename}')
         elif event['status'] == 'downloading':
diff --git a/tubesync/tubesync/settings.py b/tubesync/tubesync/settings.py
index de7a1bc..8762d4c 100644
--- a/tubesync/tubesync/settings.py
+++ b/tubesync/tubesync/settings.py
@@ -160,6 +160,9 @@ YOUTUBE_DEFAULTS = {
     'ignoreerrors': True,   # Skip on errors (such as unavailable videos in playlists)
     'cachedir': False,      # Disable on-disk caching
     'addmetadata': True,    # Embed metadata during postprocessing where available
+    'writesubtitles': True,
+    'writeautomaticsub': True,
+    'subtitleslangs': ['fr', 'en'],
 }
 COOKIES_FILE = CONFIG_BASE_DIR / 'cookies.txt'