diff --git a/variants/lilygo_t5s3_epaper_pro/CPUPowerManager.h b/variants/lilygo_t5s3_epaper_pro/CPUPowerManager.h
index 4099db8..444a90b 100644
--- a/variants/lilygo_t5s3_epaper_pro/CPUPowerManager.h
+++ b/variants/lilygo_t5s3_epaper_pro/CPUPowerManager.h
@@ -24,7 +24,7 @@
 #endif
 
 #ifndef CPU_FREQ_LOW_POWER
-#define CPU_FREQ_LOW_POWER  40 // MHz — lock screen / idle standby
+#define CPU_FREQ_LOW_POWER 80   // MHz — lock screen / idle standby (40 MHz breaks I2C)
 #endif
 
 #ifndef CPU_BOOST_TIMEOUT_MS
diff --git a/variants/lilygo_tdeck_pro/CPUPowerManager.h b/variants/lilygo_tdeck_pro/CPUPowerManager.h
index 4099db8..444a90b 100644
--- a/variants/lilygo_tdeck_pro/CPUPowerManager.h
+++ b/variants/lilygo_tdeck_pro/CPUPowerManager.h
@@ -24,7 +24,7 @@
 #endif
 
 #ifndef CPU_FREQ_LOW_POWER
-#define CPU_FREQ_LOW_POWER  40 // MHz — lock screen / idle standby
+#define CPU_FREQ_LOW_POWER 80   // MHz — lock screen / idle standby (40 MHz breaks I2C)
 #endif
 
 #ifndef CPU_BOOST_TIMEOUT_MS