Random Frequent Unknown Notifications

[BigIan279]

Something has happened to my notification on my SGS9+ phone. The last update was installed on 25th September although I doubt it has anything to do with it. Anyway, I am getting a "notification" sound which is coming in random timings but very frequently, like every minute or two. They do not come with anything telling me what the notification is for and it's driving me nuts. I don't want to turn my notifications off as I need the other ones (with different sounds). Is there a way of interrogating my phone to find out which notifications use which "sound" so hopefully I can track down what notification it is so I can switch it off. It also continues when in flight mode.

 

[Hadron]

Possibly an app update rather than a system one, so I'd check any that have been updated since shortly before it started. Especially check anything that monitors phone status: I once had a battery monitor which would "helpfully" chime whenever the battery temperature crossed some threshold, which meant randomly through the day. Took me 2 weeks to identify as there was no other indication (as it wasn't technically a notification, just an app making a sound).