Index: gtk2_ardour/mixer_strip.cc
===================================================================
--- gtk2_ardour/mixer_strip.cc	(revision 1083)
+++ gtk2_ardour/mixer_strip.cc	(working copy)
@@ -231,6 +231,12 @@
 							_("Click to Add/Edit Comments"):
 							_route->comment());
 
+	if (! _route->comment().empty()) {
+		comment_button.set_state (Gtk::STATE_ACTIVE);
+	} else {
+		comment_button.set_state (Gtk::STATE_NORMAL);
+	}
+
 	comment_button.signal_clicked().connect (mem_fun(*this, &MixerStrip::comment_button_clicked));
 	comment_button.signal_enter().connect (mem_fun(*this, &MixerStrip::comment_button_refresh));
 	comment_button.signal_leave().connect (mem_fun(*this, &MixerStrip::comment_button_refresh));