diff --git a/youtube_dl/postprocessor/ffmpeg.py b/youtube_dl/postprocessor/ffmpeg.py
index fd3f921a8..536870257 100644
--- a/youtube_dl/postprocessor/ffmpeg.py
+++ b/youtube_dl/postprocessor/ffmpeg.py
@@ -549,6 +549,9 @@ class FFmpegFixupStretchedPP(FFmpegPostProcessor):
 
         return [], info
 
+    def _configuration_args(self, default=[]):
+        return []  # Make sure the users extra arguments don't mess up the fix
+    
 
 class FFmpegFixupM4aPP(FFmpegPostProcessor):
     def run(self, info):
@@ -567,6 +570,8 @@ class FFmpegFixupM4aPP(FFmpegPostProcessor):
 
         return [], info
 
+    def _configuration_args(self, default=[]):
+        return []  # Make sure the users extra arguments don't mess up the fix
 
 class FFmpegFixupM3u8PP(FFmpegPostProcessor):
     def run(self, info):
@@ -581,6 +586,9 @@ class FFmpegFixupM3u8PP(FFmpegPostProcessor):
             os.remove(encodeFilename(filename))
             os.rename(encodeFilename(temp_filename), encodeFilename(filename))
         return [], info
+    
+    def _configuration_args(self, default=[]):
+        return []  # Make sure the users extra arguments don't mess up the fix
 
 
 class FFmpegSubtitlesConvertorPP(FFmpegPostProcessor):