diff --git a/Main.tscn b/Main.tscn
index d205819..f121a30 100644
--- a/Main.tscn
+++ b/Main.tscn
@@ -230,7 +230,7 @@ extra_spacing_bottom = 5
 font_data = ExtResource( 11 )
 _sections_unfolded = [ "Extra Spacing", "Font", "Settings" ]
 
-[node name="Main" type="WorldEnvironment"]
+[node name="Main" type="WorldEnvironment" index="0"]
 
 environment = SubResource( 2 )
 script = ExtResource( 2 )
diff --git a/MidiPlayer.gd b/MidiPlayer.gd
index 4ef3e2b..43f0954 100644
--- a/MidiPlayer.gd
+++ b/MidiPlayer.gd
@@ -3,14 +3,30 @@ extends "midi/MidiPlayer.gd"
 const Tetromino = preload("res://Tetrominos/Tetromino.gd")
 
 const LINE_CLEAR_CHANNELS = [2, 6]
-const MOVE_CHANNELS = [3]
+const MOVE_CHANNELS = [8]
+
+var muted_events = []
 
 func _ready():
 	mute_channels(MOVE_CHANNELS+LINE_CLEAR_CHANNELS)
 
+func _init_channel( ):
+	._init_channel()
+	for channel in max_channel:
+		self.muted_events.append({})
+
 func resume():
 	play(position)
+
+func _process_track_event_note_off( channel, event ):
+	muted_events[channel.number].erase(event.note)
+	._process_track_event_note_off( channel, event )
 	
+func _process_track_event_note_on( channel, event ):
+	if self.channel_mute[channel.number]:
+		muted_events[channel.number][event.note] = event
+	._process_track_event_note_on( channel, event )
+
 func mute_channels(channels):
 	for channel_id in channels:
 		channel_mute[channel_id] = true
diff --git a/midi/MidiPlayer.gd b/midi/MidiPlayer.gd
index 3de5132..d3973fd 100644
--- a/midi/MidiPlayer.gd
+++ b/midi/MidiPlayer.gd
@@ -38,9 +38,6 @@ var audio_stream_players = []
 
 var _used_program_numbers = []
 
-var muted_events = []
-var paused_position = 0
-
 signal changed_tempo( tempo )
 signal appeared_lyric( lyric )
 signal appeared_marker( marker )
@@ -180,7 +177,6 @@ func _init_channel( ):
 			"drum_track": drum_track,
 			"pan": 0.5,
 		})
-		self.muted_events.append({})
 
 """
 	再生
@@ -278,11 +274,8 @@ func _process_track( ):
 
 		match event.type:
 			SMF.MIDIEventType.note_off:
-				muted_events[event_chunk.channel_number].erase(event.note)
 				self._process_track_event_note_off( channel, event )
 			SMF.MIDIEventType.note_on:
-				if self.channel_mute[event_chunk.channel_number]:
-					muted_events[event_chunk.channel_number][event.note] = event
 				self._process_track_event_note_on( channel, event )
 			SMF.MIDIEventType.program_change:
 				channel.program = event.number