As notification channels are a must for Oreo+ APIs, then this is most probably related to the channel.
I think you can stop this sound by using
NotificationManager.IMPORTANCE_LOW while creating the Foreground service notification channel.
NotificationChannel serviceChannel = new NotificationChannel( CHANNEL_ID, CHANNEL_NAME, NotificationManager.IMPORTANCE_LOW // <<<<< ); NotificationManager manager = getSystemService(NotificationManager.class); manager.createNotificationChannel(serviceChannel);
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