diff --git a/platformio.ini b/platformio.ini
index ec73bc56..06551afd 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -511,8 +511,10 @@ upload_speed = 921600
 custom_usermods = audioreactive
 build_unflags = ${common.build_unflags}
 build_flags = ${common.build_flags} ${esp32.build_flags} -D WLED_RELEASE_NAME=\"ESP32_Ethernet\" -D RLYPIN=-1 -D WLED_USE_ETHERNET -D BTNPIN=-1
+  -D SR_DMTYPE=-1 -D AUDIOPIN=-1 -D I2S_SDPIN=-1 -D I2S_WSPIN=-1 -D I2S_CKPIN=-1 -D MCLK_PIN=-1 ;; force AR to not allocate any PINs at startup
+  -D DATA_PINS=4 ;; default led pin = 16 conflicts with pins used for ethernet
+  ; -D WLED_DISABLE_ESPNOW ;; ESP-NOW requires wifi, may crash with ethernet only => uncomment if your board uses ETH_CLOCK_GPIO0_OUT, ETH_CLOCK_GPIO16_OUT, ETH_CLOCK_GPIO17_OUT
   -DARDUINO_USB_CDC_ON_BOOT=0 ;; this flag is mandatory for "classic ESP32" when building with arduino-esp32 >=2.0.3
-;  -D WLED_DISABLE_ESPNOW ;; ESP-NOW requires wifi, may crash with ethernet only
 lib_deps = ${esp32.lib_deps}
 board_build.partitions = ${esp32.default_partitions}
 board_build.flash_mode = dio
diff --git a/wled00/const.h b/wled00/const.h
index 6d1825d5..642fc85c 100644
--- a/wled00/const.h
+++ b/wled00/const.h
@@ -611,7 +611,12 @@ static_assert(WLED_MAX_BUSSES <= 32, "WLED_MAX_BUSSES exceeds hard limit");
     #define DEFAULT_LED_PIN 2    // GPIO2 (D4) on Wemos D1 mini compatible boards, safe to use on any board
   #endif
 #else
-  #define DEFAULT_LED_PIN 16   // aligns with GPIO2 (D4) on Wemos D1 mini32 compatible boards (if it is unusable it will be reassigned in WS2812FX::finalizeInit())
+  #if defined(WLED_USE_ETHERNET)
+    #define DEFAULT_LED_PIN 4    // GPIO4 seems to be a "safe bet" for all known ethernet boards (issue #5155)
+    //#warning "Compiling with Ethernet support. The default LED pin has been changed to pin 4."
+  #else
+    #define DEFAULT_LED_PIN 16   // aligns with GPIO2 (D4) on Wemos D1 mini32 compatible boards (if it is unusable it will be reassigned in WS2812FX::finalizeInit())
+  #endif
 #endif
 #define DEFAULT_LED_TYPE TYPE_WS2812_RGB
 #define DEFAULT_LED_COUNT 30