That's the outage I saw also but it might have happened just before the problem was found.

I guess you've not looked at the extra things you have in Extended :).

If you look at the Historical menu, you'll find all of the events in there. You can even download some of the data then format it and combine it in any way that suits your needs using excel or something else.

Indeed, there could be something that is slowly failing, causing many short outages or disconnections.

Could be a cable, power supply, an interface, but keep in mind, it's always possible that it's just a tiny configuration issue too.

For example, sometimes a firewall with an upstream DHCP might show that it knows what its gateway is but might lose it at times causing short outages. Configuring a static GW might help.

I know this is not your situation so just sharing how tiny things can be hard to find and not so obvious sometimes.