Index: libao2/ao_dsound.c
===================================================================
--- libao2/ao_dsound.c  (revision 20253)
+++ libao2/ao_dsound.c  (working copy)
@@ -605,6 +605,7 @@
        if(space > buffer_size)space -= buffer_size; // write_offset < play_offset
        if(space < len) len = space;
 
+        if (!(flags & AOPLAY_FINAL_CHUNK))
        len = (len / ao_data.outburst) * ao_data.outburst;
        return write_buffer(data, len);
 }