diff --git a/js/ui/status/volume.js b/js/ui/status/volume.js
index 744d650e9..bbbfb454b 100644
--- a/js/ui/status/volume.js
+++ b/js/ui/status/volume.js
@@ -19,6 +19,9 @@ const VolumeType = {
 // Each Gvc.MixerControl is a connection to PulseAudio,
 // so it's better to make it a singleton
 let _mixerControl;
+/**
+ * @returns {Gvc.MixerControl} - the mixer control singleton
+ */
 function getMixerControl() {
     if (_mixerControl)
         return _mixerControl;