diff --git a/applet/contents/ui/main.qml b/applet/contents/ui/main.qml
--- a/applet/contents/ui/main.qml
+++ b/applet/contents/ui/main.qml
@@ -164,6 +164,14 @@
             }
 
             var icon = Icon.formFactorIcon(defaultSink.formFactor);
+            if (!icon) {
+                // Show "muted" icon for Dummy output
+                // DEFAULT_SINK_NAME in module-always-sink.c
+                if (defaultSink.name === "auto_null") {
+                    icon = "audio-volume-muted";
+                }
+            }
+
             if (!icon) {
                 icon = Icon.name(defaultSink.volume, defaultSink.muted);
             }