Sudden, Unexplained Lag with Wireless Connection

Hi, I hope someone can help.

Until sometime yesterday my router (a Virgin Super Hub 2 ac) had been working normally.
I have no idea what happened but since then Internet connection gets extremely laggy and sometimes just 'hangs' when browsing, and especially when checking for emails. I can eventually get these things to work but only after several repeated attempts or page refreshes. I'm seeing more 'timed out' errors than usual as well.

I've also got a Nintendo 3DS that connects to the same router and the lag is far more noticeable on that device, to the point where sites will only load if I keep refreshing the page, and even then it doesn't always load.

The router's lights are functioning normally and you wouldn't know anything was wrong from looking at it. According to the Virgin Media status page there aren't any problems in our area.
I originally posted this query on Virgin's community page but so far the only advice I've been given was to change the router's channel from 1 to 11 in case neighbors' connections were causing interference, but this hasn't made any difference. I'm using a wireless connection and am not in a position to use a wired connection due to how far apart the laptop is from the router.

Sorry for the long post, any advice would be greatly appreciated.

This may happen due to an intruder.Check your router page for connected devices list.
A 3rd party app that does this-Windows - Who Is On My WiFi

Hi Beowulf1,

Thank you for the link. I've checked the Router connected devices list several times over the last two days and it only ever lists my computer. I've run a scan with Who Is On My Wifi and this didn't list anything unusual either. I tried connecting with an Ethernet cable and found the lag is still a problem on a wired connection as well.

Hi, sorry for the delay in reporting this. About a week ago the problem sorted itself out, presumably another Virgin customer reported a fault in the area. Either way things are working properly again.