PortManager::silence() should not clear data in AsyncMIDIPorts

This data was generated asynchronously and is not required to be "silenced"
the way that session data would be. Compare also to the similar tests for
sync-related MIDI ports

diff --git a/libs/ardour/port_manager.cc b/libs/ardour/port_manager.cc
index 10c19a9c67547f4cd07aecbdec4f05185a06e50e..a5af8f2fe16d5e28e6c110e00c02adf6843f788b 100644 (file)
--- a/libs/ardour/port_manager.cc
+++ b/libs/ardour/port_manager.cc
@@ -684,6 +684,9 @@ PortManager::silence (pframes_t nframes, Session *s)
                if (s && i->second == s->ltc_output_port ()) {
                        continue;
                }
+               if (boost::dynamic_pointer_cast<AsyncMIDIPort>(i->second)) {
+                       continue;
+               }
                if (i->second->sends_output()) {
                        i->second->get_buffer(nframes).silence(nframes);
                }