diff --git a/gtk2_ardour/editor_ops.cc b/gtk2_ardour/editor_ops.cc
index ac1de28e8d..22d89bdf96 100644
--- a/gtk2_ardour/editor_ops.cc
+++ b/gtk2_ardour/editor_ops.cc
@@ -3390,6 +3390,25 @@ Editor::freeze_route ()
 		return;
 	}
 
+	if (clicked_routeview->track()->has_external_redirects()) {
+		MessageDialog d (string_compose (_("<b>%1</b>\n\nThis track has at least one send/insert/return as part of its signal flow.\n\n"
+						   "Freezing will only process the signal as far as the first send/insert/return."),
+						 clicked_routeview->track()->name()), true, MESSAGE_INFO, BUTTONS_NONE, true);
+
+		d.add_button (_("Freeze anyway"), Gtk::RESPONSE_OK);
+		d.add_button (_("Don't freeze"), Gtk::RESPONSE_CANCEL);
+		d.set_title (_("Freeze Limits"));
+
+		int response = d.run ();
+
+		switch (response) {
+		case Gtk::RESPONSE_CANCEL:
+			return;
+		default:
+			break;
+		}
+	}
+
 	InterThreadInfo itt;
 	current_interthread_info = &itt;
 
diff --git a/libs/ardour/ardour/route.h b/libs/ardour/ardour/route.h
index e8fbc0ed7d..42b74b50bc 100644
--- a/libs/ardour/ardour/route.h
+++ b/libs/ardour/ardour/route.h
@@ -423,6 +423,8 @@ class Route : public SessionObject, public Automatable, public RouteGroupMember,
 	void sync_order_keys (std::string const &);
 	static PBD::Signal1<void,std::string const &> SyncOrderKeys;
 
+	bool has_external_redirects() const;
+
   protected:
 	friend class Session;
 
diff --git a/libs/ardour/route.cc b/libs/ardour/route.cc
index 6f68f172a7..c726aec833 100644
--- a/libs/ardour/route.cc
+++ b/libs/ardour/route.cc
@@ -4039,3 +4039,21 @@ Route::metering_state () const
 {
 	return MeteringRoute;
 }
+
+bool
+Route::has_external_redirects () const
+{
+	for (ProcessorList::const_iterator i = _processors.begin(); i != _processors.end(); ++i) {
+
+		/* ignore inactive processors and obviously ignore the main
+		 * outs since everything has them and we don't care.
+		 */
+		 
+		if ((*i)->active() && (*i) != _main_outs && (*i)->does_routing()) {
+			return true;;
+		}
+	}
+
+	return false;
+}
+
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index 2f57af4923..934da39fc0 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -3969,13 +3969,14 @@ Session::write_one_track (AudioTrack& track, framepos_t start, framepos_t end,
 		srcs.push_back (fsource);
 	}
 
-	/* tell redirects that care that we are about to use a much larger blocksize */
+	/* tell redirects that care that we are about to use a much larger
+	 * blocksize. this will flush all plugins too, so that they are ready
+	 * to be used for this process.
+	 */
 
 	need_block_size_reset = true;
 	track.set_block_size (chunk_size);
 
-	/* XXX need to flush all redirects */
-
 	position = start;
 	to_do = len;