diff --git a/server.js b/server.js
index 828006b..3e5dda6 100644
--- a/server.js
+++ b/server.js
@@ -57,9 +57,10 @@ const server = http.Server(app);
 // Odprti serijski OSC link
 let scon = null
 
+let mo = null
 if (MIDI) {
   // Midi port
-  const mo = new midi.Output()
+  mo = new midi.Output()
   //mo.getPortCount()
   //mo.getPortName(0)
   //mo.openPort(0)