PlusNet connection feels "unreliable" despite good speed tests

[#1]

Hi all,

I wondered if anyone might be able to offer some advice on an annoying broadband/network issue I’ve been having.

I moved to PlusNet fibre broadband in 2025. Prior to this, I was with Sky fibre using exactly the same home network hardware with no issues whatsoever.

My setup under Sky was:

• Openreach HG612 modem
• Asus RT-AC68U router
• TP-Link TL-WPA7617 Powerline WiFi extender upstairs (this had the same SSID as the main router)

The TP-Link extender also provides Ethernet to my desktop PC upstairs. This setup was rock solid for years under Sky.

When I moved to PlusNet, I initially used the supplied Hub 2 as the modem/router and connected the TP-Link extender to it. After a few weeks, I started noticing that although speedtests were fine, the overall “quality” and responsiveness of the connection seemed worse.

Examples include:

• Facebook pages only partially loading, with grey placeholder boxes while scrolling
• Some webpages appearing to “half load”
• Instagram reels buffering repeatedly on both desktop and mobile
• Video calls becoming unreliable or dropping out
• Video streaming quality seeming inconsistent
• The YouTube “Cast” option intermittently disappearing
• General inconsistency

None of these are huge issues individually, but together they make the connection feel unreliable compared to how it behaved under Sky. It's also highly annoying!

Things I’ve tried so far:

• Put the PlusNet Hub 2 into modem mode and reconnected my Asus router using PPPoE credentials
• Removed the Hub entirely and reinstated the original Openreach modem with the Asus router
• Changed DNS on the Asus router from old OpenDNS settings to Cloudflare (1.1.1.1 / 1.0.0.1)
• Changed MTU to 1492
• Enabled NAT acceleration on the Asus router
• I have given the TP Link extender its own SSID/Network name

This has improved things somewhat, but the issues still seem to exist.

When I run speedtests, I get the speeds I’d expect for my package. However, latency during the download test seems to fluctuate quite a bit (typically around 60-70ms but occasionally spiking briefly into the 200-300ms range).

At this point I’m struggling to work out whether:

• there’s an issue with my PlusNet connection/routing,
• whether my old Asus RT-AC68U is simply showing its age (despite it working fine until I changed ISPs?)
• or whether there’s something else I should be looking at.

Has anyone experienced similar behaviour or got any suggestions?

Thanks in advance!

[#2]

@rjpholliday 

Are you having the same issue if connected straight to the hub? If not, the first thing that I would look at is the Tp-link extender. Is this wireless or Powerline?  Long CAT5e Ethernet cables are cheap. My first move would be to replace the link with a cable temporarily to see if that resolved the problem.

You cannot assume that its been caused by a change of ISP, there are many possibilities in play.

[#3]

@rjpholliday Wrote : Changed DNS on the Asus router from old OpenDNS settings to Cloudflare (1.1.1.1 / 1.0.0.1)

Worth checking the computer picks up the router DNS settings and not a manaual setting poiinting somewhere else..........

[#4]

@rjpholliday 

It may or may not be significant, but as I understand it, Sky have a network that prefers IPv6.

https://www.ispreview.co.uk/index.php/2024/06/isp-sky-broadband-uk-deploying-ip-address-sharing-via-...

With your Asus you probably got a connection that supported IPv4 and IPv6 (I believe Sky will give you both with a third party router).

Plusnet has no IPv6 (other than a small trial) at present.

[#5]

@Baldrick1 Thank you! Yes, I didn't want to immediately jump to it being an ISP issue.

I tried connecting my laptop directly to the router using a (short) Ethernet cable - it seemed slightly better but I was still getting download latency spikes around 150 on a speedtest and the "facebook issue" still persisted. I haven't got a long enough cable to test this with the office/desktop but I will try that when I can.

The extender is connected over Powerline, the setup is this: Openreach Modem > Asus Router > TP Link Powerline Adapter > TP Link Powerline Extender > Ethernet to desktop PC.

I am looking at changing the Asus router (it's very old) to a TP Link mesh-compatible router at some point so I don't need the separate SSID for the extender. I did previously have both router/extender on the same SSID but that isn't a proper "mesh" setup as far as I am aware; just means some manual switching now...

(I've historically had pretty poor Wifi from a single access point in this property regardless of ISP due to the construction being mainly solid concrete; this extender setup had been the most reliable solution so far...)

[#6]

@Champnet Thanks - from all the tools I'm able to use, it seems the desktop is using the Cloudflare DNS settings.

[#7]

@rjpholliday 

The acid test is to connect just the Plusnet Hub 2 in modem/router mode to the master socket with just your laptop connected via an Ethernet cable. This will tell you how well the incoming connection is performing.

[#8]

Thanks @Baldrick1 - I will do this over the weekend and let you know how I get on. Cheers once again!