diff --git a/plugins/dell-dock/fu-dell-dock-i2c-mst.c b/plugins/dell-dock/fu-dell-dock-i2c-mst.c
index 21887fb3f..a57e66bad 100644
--- a/plugins/dell-dock/fu-dell-dock-i2c-mst.c
+++ b/plugins/dell-dock/fu-dell-dock-i2c-mst.c
@@ -98,7 +98,7 @@ const MSTBankAttributes esm_attributes = {
 FuHIDI2CParameters mst_base_settings = {
     .i2cslaveaddr = I2C_MST_ADDRESS,
     .regaddrlen = 0,
-    .i2cspeed = I2C_SPEED_800K,
+    .i2cspeed = I2C_SPEED_400K,
 };
 
 struct _FuDellDockMst {