diff --git a/js/midi/io.js b/js/midi/io.js
index 1f34683..aa96b40 100644
--- a/js/midi/io.js
+++ b/js/midi/io.js
@@ -131,11 +131,11 @@
             App.MIDI.output = new Output();
             
             navigator.requestMIDIAccess().then(function (access) {
-                var outputs = access.outputs(),
+                var outputs = access.outputs,
                     output;
 
-                if (outputs && outputs.length) {
-                    output = new Output(outputs[0]);
+                if (outputs.size) {
+                    output = new Output(outputs.get(0));
                     App.MIDI.output = output;
 
                     resolve(output);