Update mpg123 library and fix decode errors crashing.

lib/workers/audio-worker.js

@@ -33,7 +33,7 @@ self.addEventListener('message', function(e) {
     // On error we still want to restore the audio file
     asset.on("error", function(error) {
         self.postMessage({arrayBuffer : arrayBuffer,
-            error: error},
+            error: String(error)},
             [arrayBuffer]);
     });