diff --git a/README.md b/README.md
index ef9620b..1d1c7d4 100644
--- a/README.md
+++ b/README.md
@@ -49,7 +49,14 @@ Master can suppress a matched standard notification alert while leaving the
 notification itself visible. Experimental per-app control is also available for
 direct vibrations that are explicitly marked by Android as notification usage.
 It deliberately does not touch media, alarms, ringtones, touch feedback, or
-unknown vibration usage.
+unknown vibration usage. Direct app-originated sounds are not intercepted: they
+do not have a safe, complete Android system boundary, so their original sound
+continues to play.
+
+To use the optional integration, enable Notifications Master as an LSPosed
+module and give it the **Android/system server** scope, then restart Android.
+Enable direct-vibration control only for apps where you want that experimental
+behaviour; normal notification rules work independently of this setting.
 
 Custom alerts respect Do Not Disturb. Android does not allow a normal app to
 force direct custom sound or vibration through Do Not Disturb.