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Wi-Fi and slow internet troubleshooting checklist (NZ)

Separate Wi-Fi from fibre, capture timestamps, and gather the evidence an ISP can actually use.

Most "slow internet" problems are not the internet. They are Wi-Fi coverage, router CPU limits, a noisy channel, a device problem, or an ISP issue that cannot be proven without timestamps and repeatable tests. This checklist is designed to shrink the problem until it has a clear fault domain.

1. Decide whether this is Wi-Fi or the fibre connection

If you only test on Wi-Fi, you cannot know where the problem lives. A wired test is the fastest truth machine.

Wired baseline

Run a speed test on Ethernet (direct to router). If wired is fine but Wi-Fi is bad, focus on Wi-Fi and placement.

One device at a time

Test one known-good device, then compare. Multiple failing devices suggests network. One failing device suggests the device.

Time of day

Record whether it is worse at peak hours. Congestion patterns matter when you escalate to an ISP.

Symptoms

Differentiate "slow", "dropouts", "buffering", "VPN disconnects", and "calls sound bad". They often have different causes.

2. Capture timestamps and a short test plan

ISPs cannot investigate "sometimes it is slow" without timestamps. Keep a simple log for 48 hours.

  • For each incident: date/time, which device, wired or Wi-Fi, and what you were doing (video call, upload, browsing).
  • Run the same speed test link each time so results are comparable.
  • Note whether a reboot "fixes it" and how long the fix lasts.
  • Take a screenshot of router/fibre light status when it fails.

Evidence matrix: match the symptom to the likely layer

The aim is not to prove blame. It is to show which layer deserves the next test: device, Wi-Fi, router, fibre, provider, or application. A simple matrix prevents random changes and makes escalation cleaner.

Wired fast, Wi-Fi slow

Focus on coverage, router placement, access-point load, channel congestion, device roaming, and whether the affected room has a weak signal.

Wired and Wi-Fi both slow

Check router load, fibre/ONT status, provider outage notices, plan speed, heavy uploads, and whether all devices are affected at the same time.

One device slow, others fine

Check device updates, Wi-Fi adapter state, VPN, security software, browser extensions, storage pressure, and whether the device behaves elsewhere.

Calls bad, browsing fine

Measure latency, jitter, packet loss, upload saturation, and whether Wi-Fi roaming or router load aligns with the bad-call timestamps.

3. Reduce Wi-Fi risk without buying new gear first

Many Wi-Fi problems are placement and interference. Try the cheap changes before the expensive ones.

Router placement

Put the router high and central. Avoid cupboards, metal cabinets, and stacked electronics.

2.4 GHz vs 5 GHz

Use 2.4 GHz for range and 5 GHz for speed. Consider separate SSIDs if devices jump between bands badly.

Channel noise

Dense areas can have congested channels. If supported, try a channel change and record whether it improves.

Mesh sanity

If using mesh, confirm backhaul quality. A mesh node with weak link can make performance worse than a single router.

4. Router and network basics worth checking

SME routers can be overwhelmed by too many devices, old firmware, or heavy VPN/VoIP load.

  • Update router firmware if your provider supports it (or note the current version if managed by the ISP).
  • Check whether the router is overheating or physically obstructed.
  • Record the device list (phones, laptops, TVs, cameras, printers). "New device added" is a real clue.
  • If VPN is used, test with VPN off once (if safe) to confirm whether VPN is the bottleneck.

NZ reference points before escalating

Provider and regulator pages can help shape the evidence pack. They will not fix a local Wi-Fi problem, but they make it easier to separate local symptoms from broadband performance and dispute/escalation paths.

Broadband performance context

The Commerce Commission's Measuring Broadband New Zealand programme is useful context for thinking about speed, latency, and service performance.

Measuring Broadband New Zealand

Fibre help

Chorus publishes fibre help and support material that can help identify whether the fibre/ONT path needs provider attention.

Chorus fibre help and support

Provider troubleshooting

Provider troubleshooting pages often ask for outage checks, router restart order, and modem/ONT light state. Capture those before calling.

One NZ broadband troubleshooting

Dispute pathway

If a telecommunications complaint stalls after reasonable provider escalation, TDR explains the independent dispute pathway for eligible NZ issues.

Telecommunications Dispute Resolution

5. Escalation evidence: what to give the ISP

A clean escalation pack makes it far more likely you will get a useful response rather than a script. The fibre and VoIP troubleshooting checklist goes deeper on evidence capture.

Incident log

Provide timestamps, symptoms, and whether it was wired or Wi-Fi.

Speed tests

Include a small set of comparable speed tests (same device, same test site, same wired/Wi-Fi state).

Router model

Share the router model and whether the fibre ONT lights were normal during incidents.

Voice evidence

If calls are affected, record call times and which devices were used. Providers often need this for traces.

Control test

Include one clean control test: same device, same test site, same room or Ethernet cable, and no other settings changed between attempts.

Rollback note

If you changed router placement, channels, SSIDs, DNS, VPN, or access-point settings, record what changed and how to put it back.

Professional context

Where this fits in the owned support cluster

This site uses a simple structure: services that describe the work, and technical articles that document how problems get isolated. If you want the hands-on follow-up, these pages are the closest match.

Current profile

About John Finnerty links this checklist to the broader Christchurch and New Zealand support context.

Project evidence

The project hub collects public project notes and case studies that sit alongside the technical guides.

Networking support

The networking support page describes common router, Wi-Fi, and routing failures in plain language.

Services overview

The services hub links the service pages that match the "hands-on" work behind these notes.

Related services

When Wi-Fi is unstable or a fibre connection is inconsistent, the fastest path is usually isolation plus an evidence pack: what was tested, when it failed, and which layer is most likely at fault.