diff --git a/flutter/android/app/src/main/kotlin/com/carriez/flutter_hbb/MainService.kt b/flutter/android/app/src/main/kotlin/com/carriez/flutter_hbb/MainService.kt
index 1c3fbce6c..78e4e451e 100644
--- a/flutter/android/app/src/main/kotlin/com/carriez/flutter_hbb/MainService.kt
+++ b/flutter/android/app/src/main/kotlin/com/carriez/flutter_hbb/MainService.kt
@@ -384,6 +384,7 @@ class MainService : Service() {
         return true
     }
 
+    @Synchronized
     fun stopCapture() {
         Log.d(logTag, "Stop Capture")
         setFrameRawEnable("video",false)