diff --git a/.luacheckrc b/.luacheckrc
new file mode 100644
index 0000000..a31b01a
--- /dev/null
+++ b/.luacheckrc
@@ -0,0 +1,2 @@
+read_globals = {"minetest", "table", "default", "pipeworks"}
+globals = {"connected_chests"}
diff --git a/LICENSE.txt b/LICENSE.txt
index 7537bfd..18f4144 100644
--- a/LICENSE.txt
+++ b/LICENSE.txt
@@ -1,2 +1,2 @@
 connected_chest_open from default
-rest WTFPL
+Content which is not copied from minetest_game is licensed under MIT.
diff --git a/init.lua b/init.lua
index 607560f..6aa60d6 100644
--- a/init.lua
+++ b/init.lua
@@ -1,6 +1,3 @@
-local load_time_start = minetest.get_us_time()
-
-
 -- param_tab maps the x and z offset to a param2 value
 local param_tab = {
 	["-1 0"] = 0,
@@ -279,7 +276,7 @@ function connected_chests.register_chest(fromname, data)
 		}
 		def_opened.diggable = false
 		def_opened.on_blast = function() end
-inside_texture = "default_chest_inside.png^([combine:16x32:5,0=" ..
+		inside_texture = "default_chest_inside.png^([combine:16x32:5,0=" ..
 			"default_chest_inside.png^connected_chests_inside_frame.png^[" ..
 			"makealpha:255,126,126)"
 		-- TODO, see right chest
@@ -475,7 +472,7 @@ local function close_chest(vi)
 	pos.x = pos.x + x * 0.5
 	pos.z = pos.z + z * 0.5
 	minetest.sound_play("default_chest_close",
-		{gain = 10.3, pos = pos, max_hear_distance = 10})
+		{gain = 0.3, pos = pos, max_hear_distance = 10, pitch = 0.7}, true)
 end
 
 -- close all remaining open chest on shutdown
@@ -521,7 +518,7 @@ connected_chests.register_chest("default:chest", {
 	add_open_chest = true,
 	on_rightclick = function(pos, _, player)
 		minetest.sound_play("default_chest_open",
-			{gain = 0.3, pos = pos, max_hear_distance = 10})
+			{gain = 0.3, pos = pos, max_hear_distance = 10, pitch = 0.7}, true)
 
 		local vi = minetest.hash_node_position(pos)
 		if not open_chests[vi]
@@ -563,12 +560,12 @@ connected_chests.register_chest("default:chest_locked", {
 	add_open_chest = true,
 	on_rightclick = function(pos, _, player)
 		if not default.can_interact_with_node(player, pos) then
-			minetest.sound_play("default_chest_locked", {pos = pos})
+			minetest.sound_play("default_chest_locked", {pos = pos}, true)
 			return
 		end
 
 		minetest.sound_play("default_chest_open",
-			{gain = 0.32, pos = pos, max_hear_distance = 10})
+			{gain = 0.32, pos = pos, max_hear_distance = 10, pitch = 0.7}, true)
 
 		local vi = minetest.hash_node_position(pos)
 		-- TODO: somehow avoid using the chest node names here
@@ -638,17 +635,3 @@ minetest.register_alias("connected_chests:chest_left_locked", "default:chest_loc
 minetest.register_alias("connected_chests:chest_right_locked", "default:chest_locked_connected_right")
 minetest.register_alias("connected_chests:chest_locked_left", "default:chest_locked_connected_left")
 minetest.register_alias("connected_chests:chest_locked_right", "default:chest_locked_connected_right")
-
---~ local function log_access(pos, player, text)
-	--~ minetest.log("action", player:get_player_name()..
-		--~ " moves stuff "..text.." at "..minetest.pos_to_string(pos))
---~ end
-
-
-local time = (minetest.get_us_time() - load_time_start) / 1000000
-local msg = "[connected_chests] loaded after ca. " .. time .. " seconds."
-if time > 0.01 then
-	print(msg)
-else
-	minetest.log("info", msg)
-end