fix: The WIFI_SERVICE must be looked up on the Application context or memory will leak on devices < Android N. Try changing to .getApplicationContext()

src/main/java/com/owncloud/android/media/MediaService.java

@@ -224,7 +224,7 @@ public class MediaService extends Service implements OnCompletionListener, OnPre
         super.onCreate();
         Log_OC.d(TAG, "Creating ownCloud media service");
 
-        mWifiLock = ((WifiManager) getSystemService(Context.WIFI_SERVICE)).
+        mWifiLock = ((WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE)).
                 createWifiLock(WifiManager.WIFI_MODE_FULL, MEDIA_WIFI_LOCK_TAG);
 
         mNotificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);