diff --git a/variants/xiao_c3/platformio.ini b/variants/xiao_c3/platformio.ini
index 6024905f..55baf2b8 100644
--- a/variants/xiao_c3/platformio.ini
+++ b/variants/xiao_c3/platformio.ini
@@ -4,6 +4,7 @@ board = seeed_xiao_esp32c3
 build_flags =
   ${esp32_base.build_flags}
   -I variants/xiao_c3
+  -D ESP32_CPU_FREQ=80
   -D LORA_TX_BOOST_PIN=D3
   -D P_LORA_TX_LED=D5
   -D PIN_VBAT_READ=D0