Rolling back some changes, due to get it running again on my dev system.

Should be made easier to change between different systems (e.g.
Teensy-4/Teensy-3, built-in SD card or audio shield SD card, ...)

SoftenValue.hpp

@@ -30,7 +30,7 @@ template <class T>
 class SoftenValue
 {
   public:
-    init(T value, T minimum, T maximum)
+    void init(T value, T minimum, T maximum)
     {
       _from = value;
       _to = value;

config.h

@@ -57,9 +57,9 @@
 //#define TEENSY_DAC
 //#define TEENSY_DAC_SYMMETRIC
 //#define TEENSY_AUDIO_BOARD
-#define I2S_AUDIO_ONLY
+//#define I2S_AUDIO_ONLY
 //#define TGA_AUDIO_BOARD
-//#define PT8211_AUDIO
+#define PT8211_AUDIO
 
 //*************************************************************************************************
 //* MIDI SETTINGS
@@ -113,24 +113,24 @@
 #define ENABLE_LCD_UI 1
 // LCD Display
 //I2C_DISPLAY only
-//#define LCD_I2C_ADDRESS 0x27
-#define LCD_I2C_ADDRESS 0x3f
+#define LCD_I2C_ADDRESS 0x27
+//#define LCD_I2C_ADDRESS 0x3f
 //Display size, must be set for U8X8 as well
 #define LCD_cols  16
-//#define LCD_rows  2
-#define LCD_rows  4
+#define LCD_rows  2
+//#define LCD_rows  4
 
 //enable U8X8 support
-#define U8X8_DISPLAY
+//#define U8X8_DISPLAY
 //enable SPI CS switching 
-#define DISPLAY_LCD_SPI
-#define U8X8_DISPLAY_CLASS U8X8_SSD1322_NHD_256X64_4W_HW_SPI
+//#define DISPLAY_LCD_SPI
+//#define U8X8_DISPLAY_CLASS U8X8_SSD1322_NHD_256X64_4W_HW_SPI
 //#define U8X8_DISPLAY_CLASS U8X8_SSD1306_128X64_NONAME_HW_I2C
-#define U8X8_CS_PIN 9
-#define U8X8_DC_PIN 15
-#define U8X8_RESET_PIN 14
+//#define U8X8_CS_PIN 9
+//#define U8X8_DC_PIN 15
+//#define U8X8_RESET_PIN 14
 //Standard 16x2 LCD display (SPI/PCF8874)
-//#define I2C_DISPLAY
+#define I2C_DISPLAY
 // [I2C] SCL: Pin 19, SDA: Pin 18 (https://www.pjrc.com/teensy/td_libs_Wire.html)
 //#define LCD_GFX 1
 #define CONTROL_RATE_MS 50
@@ -156,8 +156,7 @@
 //#define SDCARD_SCK_PIN   14
 #define SGTL5000_LINEOUT_LEVEL 29
 // Teensy 3.5 & 3.6 SD card
-//#define SDCARD_CS_PIN    BUILTIN_SDCARD
-#define SDCARD_CS_PIN    10
+#define SDCARD_CS_PIN    BUILTIN_SDCARD
 #define SDCARD_MOSI_PIN  11  // not actually used
 #define SDCARD_SCK_PIN   13  // not actually used
 
@@ -167,12 +166,12 @@
 #define ENC_L_PIN_A  3
 #define ENC_L_PIN_B  2
 #define BUT_L_PIN    4
-//#define ENC_R_PIN_A  28
-//#define ENC_R_PIN_B  29
-//#define BUT_R_PIN    30
-#define ENC_R_PIN_A  6
-#define ENC_R_PIN_B  5
-#define BUT_R_PIN    8
+#define ENC_R_PIN_A  28
+#define ENC_R_PIN_B  29
+#define BUT_R_PIN    30
+//#define ENC_R_PIN_A  6
+//#define ENC_R_PIN_B  5
+//#define BUT_R_PIN    8
 #define BUT_DEBOUNCE_MS 20
 #define LONG_BUTTON_PRESS 500