diff --git a/esp32/include/settings/peripherals_settings.h b/esp32/include/settings/peripherals_settings.h
index 6f016b0..ccdf587 100644
--- a/esp32/include/settings/peripherals_settings.h
+++ b/esp32/include/settings/peripherals_settings.h
@@ -13,7 +13,7 @@
 #define SCL_PIN SCL
 #endif
 #ifndef I2C_FREQUENCY
-#define I2C_FREQUENCY 1000000UL
+#define I2C_FREQUENCY 400000UL
 #endif
 
 // Use proto types directly