diff --git a/libs/ardour/diskstream.cc b/libs/ardour/diskstream.cc
index 0e4b5fcc49..49d9d62ec4 100644
--- a/libs/ardour/diskstream.cc
+++ b/libs/ardour/diskstream.cc
@@ -772,13 +772,7 @@ Diskstream::disengage_record_enable ()
 framecnt_t
 Diskstream::default_disk_read_chunk_frames()
 {
-#ifdef PLATFORM_WINDOWS
-	return (2 * 1048576) / sizeof (Sample);
-#elif defined __APPLE__
-	return (4 * 1048576) / sizeof (Sample);
-#else
 	return 65536;
-#endif
 }	
 
 framecnt_t