diff --git a/Marlin/Configuration_adv.h b/Marlin/Configuration_adv.h
index d8133f84..02830860 100755
--- a/Marlin/Configuration_adv.h
+++ b/Marlin/Configuration_adv.h
@@ -1772,7 +1772,7 @@
 // Without XON/XOFF flow control (see SERIAL_XON_XOFF below) 32 bytes should be enough.
 // To use flow control, set this buffer size to at least 1024 bytes.
 // :[0, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048]
-#define RX_BUFFER_SIZE 512
+#define RX_BUFFER_SIZE 256
 
 #if RX_BUFFER_SIZE >= 1024
   // Enable to have the controller send XON/XOFF control characters to