From 34936f365404a42769cb85764ecf72ae065da651 Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Thu, 3 Aug 2017 23:54:26 +0200
Subject: [PATCH] Allow calling IO::silence for yet unregistered ports (Click)

---
 libs/ardour/io.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/libs/ardour/io.cc b/libs/ardour/io.cc
index 46c5d7b8c5..a3549f0a1d 100644
--- a/libs/ardour/io.cc
+++ b/libs/ardour/io.cc
@@ -148,7 +148,9 @@ IO::silence (framecnt_t nframes)
 	/* io_lock, not taken: function must be called from Session::process() calltree */
 
 	for (PortSet::iterator i = _ports.begin(); i != _ports.end(); ++i) {
-		i->get_buffer(nframes).silence (nframes);
+		if (i->port_handle ()) {
+			i->get_buffer(nframes).silence (nframes);
+		}
 	}
 }