Internet connection instability

[Flare]

Over the past week (week and a half, maybe), my (wireless) internet connection has become very unstable - sometimes, it will run smoothly for a few hours, but other times (and, more often than not), it becomes incredibly unstable and will 'flicker' on and off repeatedly in the span of a few minutes or simply lose the connection and not regain it for a few minutes.

Current set up is:
Antenna on the roof -> this particular POE Injector -> Netgear WPN824 v2 router. Both my desktop (which is using some DELL-branded network adaptor that I can't find the model number of) and the laptops in the house are experiencing issues with the connection. The signal strength from the router is somewhat jumpy (it'll bounce between 2 and 5 bars), although I've never paid attention to the signal strength in the past.

I've tried contacting my ISP about it, but they are saying that the signal to the antenna is both strong and consistent when they tested it on their end. Could the drop in the router's signal strength be responsible for the loss of connection?

 

[Slapshot136]

it depends, are you losing your local network connection as well, or just the internet? have you tried re-starting the router?

 

[Flare]

it depends, are you losing your local network connection as well, or just the internet? have you tried re-starting the router?

I've tried restarting the router a few times over the past few days. Sometimes, it seems to improve and the connection will remain stable for a short while (maybe an hour) before going back to flickering between on and off, before going off completely for a few minutes. Other times, a router restart has had no effect at all

The network connection doesn't appear to go down - while the yellow hazard icon does appear (although, it is regularly appearing a few minutes after the internet connection goes down, then disappears shortly after appearing), I don't remember the network icon showing any signs of losing connection to the network itself.

EDIT: OK, network is still connected when the internet goes down (unless I'm interpreting the information given in the image below incorrectly )

 

[Slapshot136]

then have you tried re-starting the modem? does the internet work if you don't use the router and connect a computer directly into the modem?

 

[Flare]

then have you tried re-starting the modem? does the internet work if you don't use the router and connect a computer directly into the modem?

I've restarted the modem(?) everytime I've restarted the router since that was what the instruction leaflet that came with the router said to do

Just tried connecting my laptop directly to the cable coming from the modem - it was quite 'jerky' (I tried buffering a YouTube video at the time, and it would stop for a moment after buffering ~15-20sec of the video, then start again, and this continued for most of the video) and the connection eventually went down for about a minute.

 

[Slapshot136]

I think it's a problem with the modem then

 

[Flare]

Hmmm... apparently, it was a fault on my ISP's side after all - gave him a call this morning and there seemed to be a fault with the particular access point we were connected to. He hasn't responded with an update as he said he would, but I don't think there has been a disconnection in the last few hours so I'll assume it's sorted for now