diff --git a/src/main.cpp b/src/main.cpp
index 2e840de..866fa4c 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -266,7 +266,7 @@ TaskHandle_t fileStorageTaskHandle;
     static TwoWire i2cBusTwo = TwoWire(1);
 #endif
 #ifdef RFID_READER_TYPE_MFRC522_I2C
-    static MFRC522 mfrc522(MFRC522_ADDR, MFRC522_RST_PIN, i2cBusTwo);
+    static MFRC522 mfrc522(MFRC522_ADDR, MFRC522_RST_PIN, &i2cBusTwo);
 #endif
 
 #ifdef PORT_EXPANDER_ENABLE
@@ -276,7 +276,7 @@ TaskHandle_t fileStorageTaskHandle;
 #if (HAL == 2)
     #include "AC101.h"
     static TwoWire i2cBusOne = TwoWire(0);
-    static AC101 ac(i2cBusOne);
+    static AC101 ac(&i2cBusOne);
 #endif
 #ifdef RFID_READER_TYPE_MFRC522_SPI
     static MFRC522 mfrc522(RFID_CS, RST_PIN);
@@ -4746,7 +4746,8 @@ void setup() {
         loggerNl(serialDebug, (char *) FPSTR(rfidScannerReady), LOGLEVEL_DEBUG);
     #endif
 
-    #ifdef RFID_READER_TYPE_MFRC522_SPI
+    // Init RC522 Card-Reader 
+    #if defined(RFID_READER_TYPE_MFRC522_I2C) || defined(RFID_READER_TYPE_MFRC522_SPI)
         mfrc522.PCD_Init();
         mfrc522.PCD_SetAntennaGain(rfidGain);
         delay(50);
@@ -5061,6 +5062,7 @@ void setup() {
     #ifdef BUTTON_5_ENABLE
         pinMode(BUTTON_5, INPUT_PULLUP);
     #endif
+
     unsigned long currentTimestamp = millis();
 
     // Init rotary encoder
diff --git a/src/settings-espa1s.h b/src/settings-espa1s.h
index cc119d3..ecadca6 100644
--- a/src/settings-espa1s.h
+++ b/src/settings-espa1s.h
@@ -22,14 +22,18 @@
     #endif
 
     // RFID (via SPI; currently not supported)
-    #define RST_PIN                         99          // Not necessary but has to be set anyway; so let's use a dummy-number
-    #define RFID_CS                         21          // GPIO for chip select (RFID)
-    #define RFID_MOSI                       23          // GPIO for master out slave in (RFID)
-    #define RFID_MISO                       19          // GPIO for master in slave out (RFID)
-    #define RFID_SCK                        18          // GPIO for clock-signal (RFID)
+    #if defined(RFID_READER_TYPE_MFRC522_SPI)
+        #define RST_PIN                         99          // Not necessary but has to be set anyway; so let's use a dummy-number
+        #define RFID_CS                         21          // GPIO for chip select (RFID)
+        #define RFID_MOSI                       23          // GPIO for master out slave in (RFID)
+        #define RFID_MISO                       19          // GPIO for master in slave out (RFID)
+        #define RFID_SCK                        18          // GPIO for clock-signal (RFID)
+    #endif
 
     // RFID (via I2C)
-    #define MFRC522_RST_PIN                 12          // needed for i2c-comm  MTDI on JTAG
+    #if defined(RFID_READER_TYPE_MFRC522_I2C)
+        #define MFRC522_RST_PIN                 12          // needed for initialisation -> MTDI on JTAG header
+    #endif
 
     // I2C-configuration (necessary for RC522 [only via i2c - not spi!] or port-expander)
     #if defined(RFID_READER_TYPE_MFRC522_I2C) || defined(PORT_EXPANDER_ENABLE)
@@ -59,7 +63,7 @@
 
     // Control-buttons (set to 99 to DISABLE; 0->39 for GPIO; 100->115 for port-expander)
     #define NEXT_BUTTON                    199          // Button 0: GPIO to detect next
-    #define PREVIOUS_BUTTON                198          // Button 1: GPIO to detect previous (Important: as of 19.11.2020 changed from 33 to 2; make sure to change in SD-MMC-mode)
+    #define PREVIOUS_BUTTON                198          // Button 1: GPIO to detect previous
     #define PAUSEPLAY_BUTTON                36          // Button 2: GPIO to detect pause/play
     #define BUTTON_4                        99          // Button 4: unnamed optional button
     #define BUTTON_5                        99          // Button 5: unnamed optional button
@@ -67,13 +71,15 @@
     // Wake-up button => this also is the interrupt-pin if port-expander is enabled!
     // Please note: only RTC-GPIOs (0, 4, 12, 13, 14, 15, 25, 26, 27, 32, 33, 34, 35, 36, 39, 99) can be used! Set to 99 to DISABLE.
     // Please note #2: this button can be used as interrupt-pin for port-expander. If so, all pins connected to port-expander can wake up ESPuino.
-    #define WAKEUP_BUTTON                   DREHENCODER_BUTTON // Defines the button that is used to wake up ESPuino from deepsleep.
+    #define WAKEUP_BUTTON                   PAUSEPLAY_BUTTON // Defines the button that is used to wake up ESPuino from deepsleep.
 
     // Power-control
     #define POWER                           19          // GPIO used to drive transistor-circuit, that switches off peripheral devices while ESP32-deepsleep
 
     // (optional) Neopixel
-    #define LED_PIN                         23          // GPIO for Neopixel-signaling
+    #if defined(NEOPIXEL_ENABLE)
+        #define LED_PIN                         23          // GPIO for Neopixel-signaling
+    #endif
 
     // (optinal) Headphone-detection
     #ifdef HEADPHONE_ADJUST_ENABLE
diff --git a/src/settings.h b/src/settings.h
index 26744d8..83a1688 100644
--- a/src/settings.h
+++ b/src/settings.h
@@ -43,7 +43,7 @@
 
     //################## select SD card mode #############################
     //#define SD_MMC_1BIT_MODE              // run SD card in SD-MMC 1Bit mode
-    //#define SINGLE_SPI_ENABLE             // If only one SPI-instance should be used instead of two (not yet working!) (Works on ESP32-A1S with RFID via I2C)
+    //#define SINGLE_SPI_ENABLE             // If only one SPI-instance should be used instead of two (not yet working!)
 
 
     //################## select RFID reader ##############################
@@ -59,7 +59,7 @@
         //#define PN5180_ENABLE_LPCD        // Wakes up ESPuino if RFID-tag was applied while deepsleep is active.
     #endif
 
-    #ifdef RFID_READER_TYPE_MFRC522_SPI
+    #if defined(RFID_READER_TYPE_MFRC522_I2C) || defined(RFID_READER_TYPE_MFRC522_SPI)
         uint8_t rfidGain = 0x07 << 4;      // Sensitivity of RC522. For possible values see reference: https://forum.espuino.de/uploads/default/original/1X/9de5f8d35cbc123c1378cad1beceb3f51035cec0.png
     #endif