diff --git a/src/lib.rs b/src/lib.rs
index 7decfad..f4fb98c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -51,7 +51,6 @@ impl<W: Write + Seek> Mp4Muxer<W> {
                 width,
                 height,
                 if is_hevc { 1 } else { 0 },
-                self.str_buffer.last().unwrap().as_ptr(),
             );
         }
     }
@@ -173,7 +172,6 @@ fn write_mp4_with_audio(
                 channelcount: channel_count,
             },
         },
-        track_name: "audio".as_ptr() as *mut i8,
     };
 
     let mux = mp4wr.mux;