+ /* These two are used only in builds where SILENCE_AFTER_SECONDS was
+ * set. BecameSilent will be emitted when the audioengine goes silent.
+ * reset_silence_countdown() can be used to reset the silence
+ * countdown, whose duration will be reduced to half of its previous
+ * value.
+ */
+
+ PBD::Signal0<void> BecameSilent;
+ void reset_silence_countdown ();
+
+ void add_pending_port_deletion (Port*);
+