diff --git a/libs/ardour/ardour/midi_diskstream.h b/libs/ardour/ardour/midi_diskstream.h
index be0e0fe48c..309c275434 100644
--- a/libs/ardour/ardour/midi_diskstream.h
+++ b/libs/ardour/ardour/midi_diskstream.h
@@ -192,8 +192,8 @@ class MidiDiskstream : public Diskstream
 	boost::weak_ptr<MidiPort>    _source_port;
 	boost::shared_ptr<SMFSource> _write_source;
 	NoteMode                     _note_mode;
-	volatile gint                _frames_written_to_ringbuffer;
-	volatile gint                _frames_read_from_ringbuffer;
+	gint                         _frames_written_to_ringbuffer;
+	gint                         _frames_read_from_ringbuffer;
 	volatile gint                _frames_pending_write;
 	volatile gint                _num_captured_loops;
 
diff --git a/libs/ardour/midi_diskstream.cc b/libs/ardour/midi_diskstream.cc
index d8429fdcd1..34547cfbf7 100644
--- a/libs/ardour/midi_diskstream.cc
+++ b/libs/ardour/midi_diskstream.cc
@@ -494,8 +494,8 @@ MidiDiskstream::commit (framecnt_t playback_distance)
 		adjust_capture_position = 0;
 	}
 
-	uint32_t frames_read = g_atomic_int_get(&_frames_read_from_ringbuffer);
-	uint32_t frames_written = g_atomic_int_get(&_frames_written_to_ringbuffer);
+	uint32_t frames_read = g_atomic_int_get(const_cast<gint*>(&_frames_read_from_ringbuffer));
+	uint32_t frames_written = g_atomic_int_get(const_cast<gint*>(&_frames_written_to_ringbuffer));
 
 	/*
 	  cerr << name() << " MDS written: " << frames_written << " - read: " << frames_read <<