diff --git a/Marlin/Configuration.h b/Marlin/Configuration.h
index ba20c6c04b..71f0ca4557 100644
--- a/Marlin/Configuration.h
+++ b/Marlin/Configuration.h
@@ -348,11 +348,12 @@ const bool Z_ENDSTOPS_INVERTING = true; // set to true to invert the logic of th
   #define ULTIPANEL 
 #endif
 
-//PANELOLU2 LCD with status LEDs, separate encoder and click inputs
+// PANELOLU2 LCD with status LEDs, separate encoder and click inputs
 //#define LCD_I2C_PANELOLU2
 #ifdef LCD_I2C_PANELOLU2
-  // This uses the LiquidTWI2 library ( https://github.com/lincomatic/LiquidTWI2 )
-  // Make sure it is placed in the Arduino or Sketchbook libraries directory.
+  // This uses the LiquidTWI2 library v1.2.3 or later ( https://github.com/lincomatic/LiquidTWI2 )
+  // Make sure the LiquidTWI2 directory is placed in the Arduino or Sketchbook libraries subdirectory.
+  // (v1.2.3 no longer requires you to define PANELOLU in the LiquidTWI2.h library header file)
   // Note: The PANELOLU2 encoder click input can either be directly connected to a pin 
   //       (if BTN_ENC defined to != -1) or read through I2C (when BTN_ENC == -1). 
   #define LCD_I2C_TYPE_MCP23017
@@ -362,15 +363,16 @@ const bool Z_ENDSTOPS_INVERTING = true; // set to true to invert the logic of th
   #define ULTIPANEL 
 #endif
 
-//Panucatt VIKI LCD with status LEDs, integrated click & L/R/U/P buttons, separate encoder inputs
+// Panucatt VIKI LCD with status LEDs, integrated click & L/R/U/P buttons, separate encoder inputs
 //#define LCD_I2C_VIKI
 #ifdef LCD_I2C_VIKI
-  // This uses the LiquidTWI2 library ( https://github.com/lincomatic/LiquidTWI2 )
-  // Make sure it is placed in the Arduino or Sketchbook libraries directory.
+  // This uses the LiquidTWI2 library v1.2.3 or later ( https://github.com/lincomatic/LiquidTWI2 )
+  // Make sure the LiquidTWI2 directory is placed in the Arduino or Sketchbook libraries subdirectory.
   // Note: The pause/stop/resume LCD button pin should be connected to the Arduino
   //       BTN_ENC pin (or set BTN_ENC to -1 if not used)
   #define LCD_I2C_TYPE_MCP23017 
   #define LCD_I2C_ADDRESS 0x20 // I2C Address of the port expander
+  #define LCD_USE_I2C_BUZZER //comment out to disable buzzer on LCD (requires LiquidTWI2 v1.2.3 or later)
   #define NEWPANEL
   #define ULTIPANEL 
 #endif
diff --git a/Marlin/Marlin.pde b/Marlin/Marlin.pde
index a3ebf4756d..f7442feb7c 100644
--- a/Marlin/Marlin.pde
+++ b/Marlin/Marlin.pde
@@ -40,9 +40,6 @@
   #elif defined(LCD_I2C_TYPE_MCP23017) || defined(LCD_I2C_TYPE_MCP23008)
     #include <Wire.h>
     #include <LiquidTWI2.h>
-    #if defined(LCD_I2C_PANELOLU2) && !defined(PANELOLU2)
-      #error You must uncomment "#define PANELOLU2" in LiquidTWI2.h for LiquidTWI2.cpp to compile correctly
-    #endif
   #else
     #include <LiquidCrystal.h>
   #endif
diff --git a/Marlin/ultralcd_implementation_hitachi_HD44780.h b/Marlin/ultralcd_implementation_hitachi_HD44780.h
index c5d1e26c27..845cc33df7 100644
--- a/Marlin/ultralcd_implementation_hitachi_HD44780.h
+++ b/Marlin/ultralcd_implementation_hitachi_HD44780.h
@@ -54,11 +54,11 @@ extern volatile uint8_t buttons;  //the last checked buttons in a bit array.
   #define LCD_HAS_SLOW_BUTTONS
 
 #elif defined(LCD_I2C_PANELOLU2)
+  // encoder click can be read through I2C if not directly connected
   #if !defined(BTN_ENC) || BTN_ENC == -1 
-    // encoder click is connected through I2C (rather than directly connected)
     #define B_I2C_BTN_OFFSET 3 // (the first three bit positions reserved for EN_A, EN_B, EN_C)
   
-    #define B_MI (ENCODER_C<<B_I2C_BTN_OFFSET)
+    #define B_MI (PANELOLU2_ENCODER_C<<B_I2C_BTN_OFFSET) // requires LiquidTWI2 library v1.2.3 or later
 
     #define LCD_CLICKED (buttons&B_MI)