Fix false-positive under-run messages

Port (or Tracks) can be safely added during playback, however
the disk-reader's playback buffer is initially empty. This lead to
false-positive Underrun() signals when processing takes place
before or concurrently with re-filling the disk-buffer for the new
channels.

Now new empty buffers are ignored, and produce silence until the
initial refill is complete. There is however no per-channel
de-click in, yet.

This fixes: play some audio track, ctrl+drag a region to the
drop-zone, creating a new track while playing.

1 files changed, 2 insertions, 0 deletions

diff --git a/libs/ardour/ardour/disk_reader.h b/libs/ardour/ardour/disk_reader.h
index ffd4e2a875..2e1ab6aec6 100644
--- a/libs/ardour/ardour/disk_reader.h
+++ b/libs/ardour/ardour/disk_reader.h
@@ -123,6 +123,7 @@ protected:
 			: DiskIOProcessor::ChannelInfo (buffer_size)
 			, pre_loop_buffer (0)
 			, pre_loop_buffer_size (0)
+			, initialized (false)
 		{
 			resize (buffer_size);
 			resize_preloop (preloop_size);
@@ -134,6 +135,7 @@ protected:
 
 		Sample* pre_loop_buffer;
 		samplecnt_t pre_loop_buffer_size;
+		bool initialized;
 	};
 
 	XMLNode& state ();