diff --git a/.luacheckrc b/.luacheckrc
index 16e7350..c28dcf0 100644
--- a/.luacheckrc
+++ b/.luacheckrc
@@ -3,6 +3,11 @@ unused_args = false
 allow_defined_top = true
 max_line_length = 90
 
+ignore = {
+  "default_stone_sounds",
+	"default_metal_sounds"
+}
+
 stds.minetest = {
 	read_globals = {
 		"DIR_DELIM",
@@ -30,4 +35,5 @@ read_globals = {
 	"frame",
 	"mg",
 	"toolranks",
+	"mcl_sounds"
 }
diff --git a/init.lua b/init.lua
index 55ece12..fc47c13 100644
--- a/init.lua
+++ b/init.lua
@@ -33,15 +33,12 @@ local stone_ingredient = is_mcl_core_present and "mcl_core:stone" or "default:st
 local copper_ingredient =
 is_mcl_core_present and "mcl_copper:copper_ingot" or 'default:copper_ingot'
 
-local default_stone_sounds = nil
-local default_metal_sounds = nil
-
 if is_mcl_sounds_present then
-default_stone_sounds = mcl_sounds.node_sound_stone_defaults()
-default_metal_sounds = mcl_sounds.node_sound_metal_defaults()
+local default_stone_sounds = mcl_sounds.node_sound_stone_defaults()
+local default_metal_sounds = mcl_sounds.node_sound_metal_defaults()
 else
-default_stone_sounds = default.node_sound_stone_defaults()
-default_metal_sounds = default.node_sound_metal_defaults()
+local default_stone_sounds = default.node_sound_stone_defaults()
+local default_metal_sounds = default.node_sound_metal_defaults()
 end