diff --git a/target/linux/ath79/dts/qca9556_mikrotik_routerboard-wap-g-5hact2hnd.dts b/target/linux/ath79/dts/qca9556_mikrotik_routerboard-wap-g-5hact2hnd.dts
index 5fd4623726d..529ac1cf3b8 100644
--- a/target/linux/ath79/dts/qca9556_mikrotik_routerboard-wap-g-5hact2hnd.dts
+++ b/target/linux/ath79/dts/qca9556_mikrotik_routerboard-wap-g-5hact2hnd.dts
@@ -73,7 +73,7 @@
 	flash@0 {
 		compatible = "jedec,spi-nor";
 		reg = <0>;
-		spi-max-frequency = <50000000>;
+		spi-max-frequency = <40000000>;
 
 		partitions {
 			compatible = "fixed-partitions";