diff --git a/src/board_gruvin9x.cpp b/src/board_gruvin9x.cpp
index d2a1ba172..25c0aa935 100644
--- a/src/board_gruvin9x.cpp
+++ b/src/board_gruvin9x.cpp
@@ -145,14 +145,16 @@ ISR(USART1_RX_vect)
   /* Filter the 9th bit, then return */
   resh = (resh >> 1) & 0x01;
   res = ((resh << 8) | resl);  
-  if((res & 0x100) == 0x100){
-    vpotToChange = res & 0xff;
+  if((res == 0x181) | (res == 0x1C1)){         //button REb filter
+    keys[BTN_REb].input((res & 0x1C1) == 0x1C1, BTN_REb);
+  } else if((res & 0x100) == 0x100){  //rotary filter
+    vpotToChange = res & 0xEF;
     vpot_mod_state = 1;
   }
   else {
     if(vpot_mod_state & (vpotToChange>0) & (vpotToChange<=NUM_UART_ROTARY_ENCODERS))
     {
-      int8_t vpot_inc = res & 0xff;
+      int8_t vpot_inc = res & 0xFF;
       if(vpot_inc){
         incRotaryEncoder((NUM_ROTARY_ENCODERS - NUM_UART_ROTARY_ENCODERS) + (vpotToChange - 1), vpot_inc);
       }