diff --git a/src/extensions/scratch3_music/index.js b/src/extensions/scratch3_music/index.js
index b209e3cde..fc07b6479 100644
--- a/src/extensions/scratch3_music/index.js
+++ b/src/extensions/scratch3_music/index.js
@@ -458,6 +458,7 @@ class Scratch3MusicBlocks {
      */
     _playDrumNum (util, drumNum) {
         if (util.target.audioPlayer === null) return;
+        // If we're playing too many sounds, do not play the drum sound.
         if (this._drumConcurrencyCounter > Scratch3MusicBlocks.CONCURRENCY_LIMIT) {
             return;
         }