handle internal-sends from audio to midi busses

diff --git a/libs/ardour/internal_send.cc b/libs/ardour/internal_send.cc
index 6a21e2b5ac7b8daeb06d6a8e35bf3d82225e02e7..67b0a06b79780aca7251e302500ca1ad811a59ee 100644 (file)
--- a/libs/ardour/internal_send.cc
+++ b/libs/ardour/internal_send.cc
@@ -144,7 +144,9 @@ InternalSend::run (BufferSet& bufs, framepos_t start_frame, framepos_t end_frame
        // in-place, which a send must never do.
 
        if (_panshell && !_panshell->bypassed() && role() != Listen) {
-               _panshell->run (bufs, mixbufs, start_frame, end_frame, nframes);
+               if (mixbufs.count ().n_audio () > 0) {
+                       _panshell->run (bufs, mixbufs, start_frame, end_frame, nframes);
+               }
 
                /* non-audio data will not have been copied by the panner, do it now
                 * if there are more buffers available than send buffers, ignore them,