Strange alien like sound notification but no notification

[Vixxen]

So, my Note 10+ has been making some strange sounds sporadically. My phone could be sitting on the table and all of a sudden it makes a strange noise - when checked no notifications. I have turned off NFC & notification reminders. This used to happen on my Galaxy S8+ too. I think it sounds like a sci-fi laser gun sound. Its irritating and wakes me up in the middle if the night! Also if my phone is on silent/vibrate it will vibrate once. 

Does anyone one have the same? or know what it may be? 

[BandOfBrothers]

If nothing is showing in your phones settings @Vixxen  then this could be a downloaded app.

To test this theory put your phone in Safe Mode which disables any downloaded apps and leaves the stock ones working and then see what happens.

[DannyT]

If it turns out this is a third party app. You can check which app it is by checking the recently used apps in the Play Store.

In order to provide a notification tone, the app will need to be active on your phone.

After the problem occurs, you can go into the Play Store to see which apps have been recently active. This should help you narrow it down, especially if it shows an app that you know you haven't used recently.  You can see which apps have been recently active, and uninstall them by opening the Play Store, then going to Menu (three lines) > My apps & games > Installed > Sort by > Last used.

[Elisapdx]

My phone recently started doing this as well sending weird noises but there is no notification. I have checked apps that I have used I have uninstalled apps as well and it still doesn't. Even if I have my phone on do not disturb it will still make that noise. I'm curious to know why and to get it to stop

[Amaken100]

I get this too. My Note lite makes strange sounds that wake me up in the middle of the night.

I went to Google Play to check recent apps. The only one it might have been is Samsung Gallery, and I've unchecked a notification button in there. So will wait to see if that works.

The other strange thing is that a friend forwarded me an audio recording via Whats App.

When I play the audio, I can hear it. But there's a really, really loud alarm sound on my phone that plays over the message.

Like .. Du du DE du du... du du De du du... and it won't stop. 

After messing about for ages... I found by selecting 'Group Media' on What's App - I could find the recording and play it without the really annoying alarm sound.

So this means the really loud alarm - is coming from my phone - and not from the audio recording. Why?*??!! does my phone do that.

[TattsGreen]

Has anyone worked out what this night time noise? I'm fed up with it waking me up

[Members_KoULg1k]

I had this problem with Samsung 8+ and Note 8

[Armzim]

Hi i am having same problem only it first sounds like a gun loading like then siren and its loud just embarrassing when i m in a meeting or doctor

[Armzim]

I m using note 20 ultra 5g 512gb please assist if u can

[JButler]

This is your notification reminder. An Accessibility tool. It's different than the basic notification alert. It's a strange and obnoxious sound that comes on every 3 minutes to remind you of a notification. Even if you think you read them all, sometimes it could be something hidden from sight. 

Ago to ACCESSIBILITY under SETTINGS. Click ADVANCED click NOTIFICATION REMINDERS. On some phones, this is under "Looking for something else" at the very bottom of the menu. Click NOTIFICATION REMINDERS and turn them off. 

This should cure that gosh-awful sound.