diff --git a/IO_OLEDDisplay.h b/IO_OLEDDisplay.h
index e158cd9..b3fa283 100644
--- a/IO_OLEDDisplay.h
+++ b/IO_OLEDDisplay.h
@@ -100,7 +100,7 @@ protected:
 
       // First clear the entire screen
       oled->clearNative();
-      
+
       // Set first two lines on screen
       LCD(0,F("DCC++ EX v%S"),F(VERSION));
       LCD(1,F("Lic GPLv3"));
@@ -115,6 +115,7 @@ protected:
   // for I2C to complete.
   /////////////////////////////////////////////////
   DisplayInterface* loop2(bool force) override {
+    (void)force;   // suppress compiler warning
 
     // Loop through the buffer and if a row has changed
     // (rowGeneration[row] is changed) then start writing the
diff --git a/IO_PCA9685pwm.h b/IO_PCA9685pwm.h
index 5a28f6e..72884a9 100644
--- a/IO_PCA9685pwm.h
+++ b/IO_PCA9685pwm.h
@@ -98,7 +98,8 @@ private:
 
   // Device-specific writeAnalogue function, invoked from IODevice::writeAnalogue().
   //            
-  void _writeAnalogue(VPIN vpin, int value, uint8_t profile, uint16_t duration) override {
+  void _writeAnalogue(VPIN vpin, int value, uint8_t param1, uint16_t param2) override {
+    (void)param1; (void)param2;  // suppress compiler warning
     #ifdef DIAG_IO
     DIAG(F("PCA9685pwm WriteAnalogue Vpin:%d Value:%d Profile:%d Duration:%d %S"), 
       vpin, value, profile, duration, _deviceState == DEVSTATE_FAILED?F("DEVSTATE_FAILED"):F(""));