diff --git a/src/mainboard/system76/addw2/devicetree.cb b/src/mainboard/system76/addw2/devicetree.cb
index bb3403ab08..28d66a5b26 100644
--- a/src/mainboard/system76/addw2/devicetree.cb
+++ b/src/mainboard/system76/addw2/devicetree.cb
@@ -14,7 +14,7 @@ chip soc/intel/cannonlake
 	register "SendVrMbxCmd" = "2"
 
 # ACPI (soc/intel/cannonlake/acpi.c)
-	# Enable s0ix
+	# Disable s0ix
 	register "s0ix_enable" = "0"
 
 	# PM Timer Enabled
@@ -46,7 +46,7 @@ chip soc/intel/cannonlake
 	# Serial I/O
 	register "SerialIoDevMode" = "{
 		[PchSerialIoIndexI2C0] = PchSerialIoPci, // Touchpad I2C bus
-		[PchSerialIoIndexI2C1] = PchSerialIoPci, // USB-C and Thunderbolt
+		[PchSerialIoIndexI2C1] = PchSerialIoDisabled,
 		[PchSerialIoIndexI2C2] = PchSerialIoDisabled,
 		[PchSerialIoIndexI2C3] = PchSerialIoDisabled,
 		[PchSerialIoIndexI2C4] = PchSerialIoDisabled,
@@ -84,8 +84,8 @@ chip soc/intel/cannonlake
 	# Audio
 	register "PchHdaDspEnable" = "0"
 	register "PchHdaAudioLinkHda" = "1"
-	register "PchHdaAudioLinkDmic0" = "1"
-	register "PchHdaAudioLinkDmic1" = "1"
+	register "PchHdaAudioLinkDmic0" = "0"
+	register "PchHdaAudioLinkDmic1" = "0"
 	register "PchHdaAudioLinkSsp0" = "0"
 	register "PchHdaAudioLinkSsp1" = "0"
 	register "PchHdaAudioLinkSsp2" = "0"
@@ -269,7 +269,7 @@ chip soc/intel/cannonlake
 				device i2c 2c on end
 			end
 		end # I2C #0
-		device pci 15.1 on  end # I2C #1
+		device pci 15.1 off end # I2C #1
 		device pci 15.2 off end # I2C #2
 		device pci 15.3 off end # I2C #3
 		device pci 16.0 off end # Management Engine Interface 1