diff --git a/firmware/platformio.ini b/firmware/platformio.ini
index 1013144..c3f8741 100644
--- a/firmware/platformio.ini
+++ b/firmware/platformio.ini
@@ -9,9 +9,11 @@
 ; https://docs.platformio.org/page/projectconf.html
 
 [env:pico]
-platform = raspberrypi
+platform = https://github.com/maxgerhardt/platform-raspberrypi.git
 board = pico
 framework = arduino
+board_build.core = earlephilhower
+board_build.filesystem_size = 0.5m
 lib_deps =
   ; khoih-prog/RP2040_SD@^1.0.1
 
diff --git a/firmware/src/audio.cpp b/firmware/src/audio.cpp
index 378a0cd..5bf4bc5 100644
--- a/firmware/src/audio.cpp
+++ b/firmware/src/audio.cpp
@@ -64,7 +64,7 @@ void init_audio() {
 
     pwm_config_set_clkdiv(&config, AUDIO_CLK_DIV);
     pwm_config_set_wrap(&config, 250);
-    pwm_init(audio_pin_slice, 0, &config, true);
+    pwm_init(audio_pin_slice, /*0,*/ &config, true);
 
     pwm_set_gpio_level(AUDIO_PIN, 0);
 }
diff --git a/firmware/src/leds.cpp b/firmware/src/leds.cpp
index 18f8ba1..e1f1d81 100644
--- a/firmware/src/leds.cpp
+++ b/firmware/src/leds.cpp
@@ -1,6 +1,5 @@
 #include <Arduino.h>
 #include "hardware/gpio.h"
-#include "mbed_wait_api.h"
 #include "pico/multicore.h"
 #include "hardware/pio.h"
 
@@ -16,8 +15,7 @@ uint row_sm = 255; // invalid
 inline void pulsePin(uint8_t pin) {
   gpio_put(pin, HIGH);
    // there are glitches without this (maybe just due to breadboard...)
-  _NOP();
-  _NOP();
+  asm volatile("nop \n nop \n nop");
   gpio_put(pin, LOW);
 }
 
diff --git a/firmware/src/sd.cpp b/firmware/src/sd.cpp
index e7d47b4..d2b8964 100644
--- a/firmware/src/sd.cpp
+++ b/firmware/src/sd.cpp
@@ -7,6 +7,7 @@
 
 #define SD_DET_PIN 28
 
+/*
 #if PIN_SPI_SS != 17
 #error "PIN_SPI_SS must be 17"
 #endif
@@ -19,15 +20,18 @@
 #if PIN_SPI_MISO != 16
 #error "PIN_SPI_MISO must be 16"
 #endif
+*/
 
 void setupSDPins() {
   // TODO: Is that even needed if we use built-in SPI?
+  /*
   pinMode(PIN_SPI_MISO, INPUT);
   pinMode(PIN_SPI_SS, OUTPUT);
   digitalWrite(PIN_SPI_SS, HIGH);
   pinMode(PIN_SPI_SCK, OUTPUT);
   pinMode(PIN_SPI_MOSI, OUTPUT);
   pinMode(SD_DET_PIN, INPUT_PULLUP);
+  */
 }
 
 bool isSDCardInserted() {
@@ -298,6 +302,7 @@ void sd_loadNextAudio() {
 }
 
 bool sd_loadGfxFrameLengths(size_t index) {
+  return false;
   /*
   if (index >= playlistSize) {
     Serial.println("Index out of range");
@@ -337,6 +342,7 @@ bool sd_loadGfxFrameLengths(size_t index) {
 uint16_t frameIdx = 0;
 
 bool sd_loadGfxBlob(size_t index) {
+  return false;
   /*
   if (index >= playlistSize) {
     Serial.println("Index out of range");
@@ -361,6 +367,7 @@ bool sd_loadGfxBlob(size_t index) {
 
 // Returns size of frame read or -1 if error
 int32_t sd_loadNextFrame() {
+  return -1;
   /*
   if (frameIdx > 0) {
     // return -1;