Relax assertion to allow rolling backwards into 0.

diff --git a/libs/ardour/route.cc b/libs/ardour/route.cc
index 6b1a73c088e588ba0b6e9c82e333b9c4e5af41f8..2ebdb95aa775dec372e783c1b044a2c92e2699fa 100644 (file)
--- a/libs/ardour/route.cc
+++ b/libs/ardour/route.cc
@@ -379,7 +379,7 @@ Route::process_output_buffers (BufferSet& bufs,
         *
         * playback_latency() is guarnteed to be <= _signal_latency + _output->latency ()
         */
-       assert (!_disk_reader || !run_disk_reader || start_sample >= 0);
+       assert (!_disk_reader || !run_disk_reader || start_sample >= 0 || speed < 0);
 
        /* however the disk-writer may need to pick up output from other tracks
         * during pre-roll (in particular if this route has latent effects after the disk).