diff --git a/system.prop b/system.prop
index fb55295..5b7db3e 100644
--- a/system.prop
+++ b/system.prop
@@ -56,3 +56,4 @@ persist.thermal.monitor=true
 
 # UMS
 persist.sys.usb.config=mass_storage,adb
+ro.vold.umsdirtyratio=40