From ec49e351c3dd67442c41663ac3af58d31885171a Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Wed, 4 Jun 2014 16:54:17 +0200
Subject: [PATCH] fixes to change engines while Ardour is running.

When a new backend is selected, it is loaded to query
available devices etc. This effectively drops the current backend.
---
 gtk2_ardour/engine_dialog.cc | 1 +
 libs/ardour/audioengine.cc   | 3 ++-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/gtk2_ardour/engine_dialog.cc b/gtk2_ardour/engine_dialog.cc
index 0a958cba87..845c6da228 100644
--- a/gtk2_ardour/engine_dialog.cc
+++ b/gtk2_ardour/engine_dialog.cc
@@ -682,6 +682,7 @@ EngineControl::EngineControl ()
 			 midi_option_combo.set_sensitive (false);
 		 }
 	 }
+	 started_at_least_once = false;
 
 	 if (!ignore_changes) {
 		 maybe_display_saved_state ();
diff --git a/libs/ardour/audioengine.cc b/libs/ardour/audioengine.cc
index 77d7731edf..d9e6da2e04 100644
--- a/libs/ardour/audioengine.cc
+++ b/libs/ardour/audioengine.cc
@@ -564,8 +564,9 @@ AudioEngine::drop_backend ()
 {
 	if (_backend) {
 		_backend->stop ();
-        _backend->drop_device();
+		_backend->drop_device();
 		_backend.reset ();
+		_running = false;
 	}
 }