diff --git a/js/midi/plugin.webaudio.js b/js/midi/plugin.webaudio.js
index 15a6f0a7..da616311 100644
--- a/js/midi/plugin.webaudio.js
+++ b/js/midi/plugin.webaudio.js
@@ -189,8 +189,8 @@
 					delay += ctx.currentTime;
 				}
 				var source = sources[sid];
-				source.gain.linearRampToValueAtTime(1, delay);
-				source.gain.linearRampToValueAtTime(0, delay + 0.3);
+				source.gainNode.gain.linearRampToValueAtTime(1, delay);
+				source.gainNode.gain.linearRampToValueAtTime(0, delay + 0.3);
 				if (source.noteOff) { // old api
 					source.noteOff(delay + 0.3);
 				} else { // new api