A DNS problem produces one of the more confusing symptoms in networking: your connection is clearly working, but websites won’t load and you get errors like “server not found” or “this site can’t be reached”.

What DNS actually does

DNS is the internet’s address book. When you type a website name, your device asks a DNS server to translate that name into the numeric address computers actually use. If that lookup fails, nothing loads — even though your connection is perfectly healthy.

It’s the equivalent of having a working phone but no contacts list.

How to recognise a DNS problem

• Websites fail with “server not found”, “DNS server not responding” or “this site can’t be reached”.
• Some sites load and others don’t, with no obvious pattern.
• Apps that connect directly — some games, some messaging apps — keep working while browsing fails.
• The connection tests fine on a speed test but browsing doesn’t work.
• Everything works if you type a numeric address directly.

Confirming it’s DNS

1. Try a different browser. Rules out a browser-specific problem.
2. Try the same site on your phone using mobile data. If it works there but not on your connection, the problem is at your end.
3. Try a numeric address. If a numeric address loads a page but names don’t, that is DNS, definitively.
4. Check whether it affects every device. One device suggests a local setting; all devices suggests the router or upstream.

Fixing it

1. Restart your router. Unplug for 30 seconds. This clears the router’s DNS cache and resolves a good proportion of cases.
2. Clear your device’s DNS cache. On Windows, open Command Prompt and run ipconfig /flushdns. On macOS, restarting is usually easiest.
3. Restart the device. Clears cached lookups and stale network state.
4. Try a different DNS provider temporarily. Setting your device or router to a public resolver such as 1.1.1.1 or 8.8.8.8 is a useful diagnostic. If that fixes it, tell us — it points to something we should look at.
5. Disable any VPN or proxy temporarily. These commonly override DNS settings and break name resolution when they disconnect untidily.
6. Check for security software that filters DNS. Some antivirus and parental-control tools block lookups.

When only one site fails

If everything works except one particular website, the problem is almost certainly at that website’s end. Confirm by trying it on mobile data or asking someone else to load it. There is nothing to fix on your side.

When to report it

Report a DNS problem to us if it affects every device, persists after restarting, or recurs regularly. Include the exact error message, whether a public resolver fixes it, and whether it affects all sites or only some.

If none of this resolves the problem, log a fault with our technical team and we’ll take it from there.

Speed isn’t everything. A 100 Mbps connection with high latency will feel worse for gaming and video calls than a 20 Mbps connection with low latency.

This guide explains what latency and jitter are, and what genuinely improves them.

What the numbers mean

• Latency (ping) is the round-trip delay, measured in milliseconds. Under 30 ms is excellent, under 60 ms is good, over 100 ms becomes noticeable in games and calls.
• Jitter is how much the latency varies. Low jitter keeps voice and video smooth. High jitter causes calls to break up even when the average latency looks fine.
• Packet loss is data that never arrives. Even 1–2% causes stuttering audio and rubber-banding in games. It is the most damaging of the three.

You can measure all of these with our speed test.

What causes high latency

The single biggest improvement: use a cable

For gaming consoles, desktop computers and any device used for serious video conferencing, an Ethernet cable is transformative. Wi-Fi introduces both latency and jitter by its nature, and no amount of tuning eliminates that entirely.

If running a cable across the room isn’t practical, at least make sure the device is on the 5 GHz band and close to the router.

Manage what else is running

• A large download or cloud backup will add latency to everything else, even if plenty of bandwidth remains.
• Schedule game and system updates overnight.
• Video calls are sensitive to jitter; ask others to pause streaming during an important call.
• If your router supports Quality of Service (QoS), prioritise gaming or voice traffic. Configure it carefully — a badly set QoS rule makes things worse.

Specifically for gaming

• Choose the closest server region. Most latency in online gaming is simple geography. A server in Europe will always feel worse than one in South Africa, regardless of your line.
• Use a cable. This is worth repeating.
• Close background applications on the gaming device, especially streaming and download clients.
• Don’t use a VPN for gaming unless you specifically need one — it adds latency by routing traffic further.
• Watch for packet loss rather than ping. Rubber-banding and teleporting players indicate loss, not high ping.

Specifically for video calls

• Upload speed matters as much as download — your video is going the other way.
• Jitter is what causes robotic audio and frozen video. A cable is the best remedy.
• Turn off video briefly if the call degrades; audio needs far less bandwidth and recovers first.
• Sit closer to the router, or move stationary equipment to cable to free up airspace.

When to report it

Report high latency to us if it’s present on a cabled device, is consistent rather than occasional, or comes with packet loss. Include latency and jitter figures with the times you measured them, and note whether the problem affects all destinations or only some.

If none of this resolves the problem, log a fault with our technical team and we’ll take it from there.

When the internet stops completely, there’s a logical order to checking things that finds the cause fastest. This is the sequence our own technicians follow.

Work through it from the top. Don’t skip ahead — the early steps are quick and eliminate the most common causes.

1. Check for a known outage

Before touching anything, look at our network status page on your phone’s mobile data. If your area is listed, we already know and are working on it.

2. Establish the scope

• Is it every device, or just one? If everything else works, the problem is that one device.
• Does a cabled device work? If yes, the connection is fine and the problem is your Wi-Fi.
• Can you reach the router’s admin page? If yes, your local network is fine and the problem is upstream.

3. Check power and lights

1. Confirm both units are powered. The ONT (or wireless radio) and the router should both have lights on.
2. Check the wall socket. Try a different socket, or test the socket with something else. Failed adapters and dead sockets are more common than people expect.
3. Look at the ONT lights. Power should be solid green, PON solid green, LOS completely off. A red LOS light means a line fault — see our fibre troubleshooting guide and report it.
4. Look at the router lights. The internet or WAN light should be lit. If it’s off, the router isn’t receiving a feed.
5. Photograph the lights before changing anything. It’s the most useful thing you can attach to a fault report.

4. Restart everything, in the right order

Order and timing matter here more than people expect. Restarting both units simultaneously is the reason many reboots appear not to work.

1. Unplug both the ONT and the router from the power. Unplug them — don’t just use the power switch.
2. Wait 30 seconds. This lets capacitors discharge and the session clear at our end.
3. Plug the ONT back in first. Wait two full minutes for its lights to settle. Be patient — this step is routinely rushed.
4. Only then plug the router back in. Give it another one to two minutes to start fully.
5. Test on a cabled device before testing Wi-Fi.

5. Check the cables

• The network cable between the ONT and router should click firmly into both ends.
• It must go into the router’s WAN or Internet port — usually a different colour from the LAN ports.
• Try a different network cable if you have one. Cables do fail, particularly where they’ve been pinched behind furniture.
• Check for visible damage to any cable, especially where it enters the building or runs along a wall.

6. Check your account

A suspended account looks exactly like a technical fault from the customer’s side. Log in to the client portal or check your email for any notice about an unpaid invoice. If the account has been restricted, see failed payments and reconnection.

7. Report the fault

If you’ve worked through all of the above and you’re still offline, it’s time for us.

• A photo of the ONT and router lights
• When the problem started
• Whether all devices are affected
• Whether a cabled device works
• Everything you’ve already tried
• A phone number we can reach you on today

Log the fault here. If you’re a business or enterprise customer and completely offline, phone us instead — it’s faster.

“Have you tried turning it off and on again?” is a cliché because it works. But there is a right and a wrong way to do it, and doing it wrongly is why many people conclude that restarting “doesn’t help”.

Why order and timing matter

Your ONT establishes a session with our network, and your router then establishes a session with the ONT. If both come back at the same time, the router frequently tries to connect before the ONT has finished registering, and fails.

Powering the ONT first and giving it time to settle before the router comes up removes that race entirely.

The correct sequence

1. Unplug both units from the power. Physically unplug them at the wall or from the back of the unit — a power switch isn’t always a true power cut.
2. Wait 30 seconds. This allows capacitors to discharge fully and the session to clear at our end. Ten seconds isn’t enough.
3. Plug the ONT back in first. On fibre installations this is the small box with the fibre cable going into it. On wireless installations it’s the power injector for the outdoor radio.
4. Wait two full minutes. Watch the lights settle. PON should go solid green, LOS should stay off. Rushing this step is the most common mistake.
5. Plug the router back in. Give it another one to two minutes to boot completely.
6. Test on a cabled device first, then Wi-Fi.

Restarting is not resetting

How often should you restart?

• Not daily. Routers are designed to run continuously, and constant reconnection is harder on them than staying up.
• Every month or two is reasonable maintenance, clearing accumulated memory issues.
• When something is misbehaving — devices dropping off, speeds inexplicably poor, or the router unresponsive.
• After a power failure, if things don’t come back correctly on their own.
• If you restart daily to keep things working, that’s a symptom of an underlying fault. Report it rather than living with it.

If restarting doesn’t help

Move on to the full no-connection checklist, which covers lights, cables, scope and account status in order. If that doesn’t resolve it either, log a fault with a photo of your equipment lights.

“The internet is slow” can mean half a dozen different things with completely different causes. This guide gives you a method for narrowing it down, which is far more useful than a list of random fixes.

Work through it in order. Each step eliminates a whole category of cause.

Step 1: Is it everything, or just one thing?

This single question eliminates most possibilities immediately.

• Only one website or app is slow? The problem is almost certainly at their end, not yours. Try a different site to confirm.
• Only one device is slow? The problem is that device — skip to step 4.
• Everything on Wi-Fi is slow but a cabled device is fine? It’s your Wi-Fi — skip to step 3.
• Everything is slow, including on a cable? Continue to step 2.

Step 2: Check for a known incident

Look at our network status page. If there’s an incident affecting your area, it’s listed there with updates. No amount of troubleshooting at your end will help.

Step 3: Establish a baseline on a cable

1. Plug a laptop directly into the router with an Ethernet cable. This is the most important step in the whole guide.
2. Pause everything else — downloads, streaming, backups, console updates — on every device.
3. Run a speed test and note the result along with the time.
4. Compare it to your package. Close to your package speed means the line is healthy and the problem is on your side of the router. Well below at all times of day is worth reporting.
5. Repeat at a different time — ideally once during the evening peak and once late at night.

Step 4: Rule out the device

• Test a second device in the same place. If one is slow and others are fine, the device is the problem.
• Restart the slow device. Fixes a surprising proportion of cases.
• Check its network port speed. Older laptops have 100 Mbps ports, capping them around 94 Mbps regardless of your line.
• Check its Wi-Fi capability. Devices more than a few years old may only support 2.4 GHz, which limits real-world speed considerably.
• Look at background activity. System updates, cloud sync and antivirus scans all consume bandwidth quietly.
• Check available storage and memory. A device running low on either performs badly at everything, including networking.

Step 5: Look at your Wi-Fi

If cabled speeds are good and Wi-Fi speeds aren’t, the connection is fine and the wireless network needs attention.

• Move the router somewhere central, high and in the open.
• Use the 5 GHz band for nearby devices.
• Change the 2.4 GHz channel to 1, 6 or 11.
• Reduce the number of connected devices.
• Consider mesh or an access point for a larger home.

Our Wi-Fi signal guide covers each of these in detail.

Step 6: Account for your household

Home packages are shared. Before concluding there’s a fault, check what else is consuming the connection:

Two 4K streams and a game update will comfortably saturate a 40 Mbps package. That isn’t a fault — it’s arithmetic.

Step 7: Report it properly

If you’ve worked through the above and cabled speeds are consistently poor, log a fault. Include:

• Three or more speed test results with the time of day
• Whether each was on cable or Wi-Fi
• Which devices are affected and which aren’t
• Whether it’s constant or follows a daily pattern
• What you’ve already tried

That level of detail routinely turns a multi-day investigation into a same-day fix.