Help when fibre is slow, unstable, or hard to explain

Fibre issues I can help narrow down

How fibre faults are separated from local network faults

Fibre troubleshooting works best when the layers are tested in order. A slow laptop on Wi-Fi can look like a fibre problem, but the real issue might be wireless coverage, an overloaded router, a damaged Ethernet lead, a single device, or a plan-speed mismatch. The first pass is to compare a wired test, a Wi-Fi test, the router status, and the timing of the issue before making assumptions.

If wired tests are also unstable, the focus shifts to the ONT handoff, router WAN settings, service-provider status, physical cabling, and whether the problem is constant or intermittent. That distinction matters because intermittent faults need timestamps and repeatable evidence, while constant faults can usually be narrowed down with a smaller set of checks.

Before contacting the ISP

• Record the time, duration, affected devices, and whether wired and Wi-Fi devices behaved differently.
• Capture the router and ONT light state before rebooting anything.
• Run one comparable speed test on Ethernet where possible, then compare it with Wi-Fi from the normal work area.
• Note recent changes such as a new router, moved ONT cable, power cut, firmware update, or changed fibre plan.
• Keep the summary short enough that support can see what has already been ruled out.

Fibre fault isolation order

A fibre fault note is strongest when it separates the local network from the provider path. Start with one known-good device, one known-good Ethernet cable, and one test close to the router. Then compare that result with Wi-Fi in the normal work area. If Ethernet is stable and Wi-Fi is not, the next page to use is Wi-Fi support Christchurch. If Ethernet is unstable too, the focus shifts to the ONT, router WAN state, cabling, outage pattern, provider ticket, and plan details.

ONT and router evidence to capture

The ONT is the fibre handoff point. It is separate from the Wi-Fi router, even when they sit beside each other. A support note should say which ONT/router lights were visible, whether the router showed an active WAN connection, whether all devices were affected, and whether the issue recovered without a restart.

• Photograph or write down ONT and router lights before unplugging anything.
• Check whether the router is connected to the expected ONT port and whether the Ethernet lead is seated properly.
• Record whether phones, EFTPOS, VPN, cloud apps, or video calls failed at the same time as general browsing.
• Capture one controlled restart order if needed: ONT, router, switches/access points, then end devices.
• Keep provider ticket numbers, promised callbacks, and any replacement-router or line-test notes in one place.

Slow, patchy, or intermittent fibre

Slow fibre can be an upstream service issue, but it can also be peak-time congestion, router limits, Wi-Fi performance, overloaded upload, a damaged cable, or a plan that does not match the real device setup. For intermittent issues, repeated proof matters more than one perfect test.

Escalation note template

A short evidence note can make provider support more productive. Keep it factual: date and time, affected devices, wired result, Wi-Fi result, ONT/router lights, service impact, restart result, and the outcome you are asking for.

• Issue: slow speeds / dropouts / no connection / voice failure / VPN failure.
• Scope: one device, one room, all Wi-Fi, all wired, all services, or only one provider/application.
• Evidence: screenshots, timestamps, speed tests, ping/traceroute if available, and ONT/router light notes.
• Actions already taken: cable swap, wired test, one controlled restart, router check, provider outage check.
• Requested outcome: line test, plan check, router replacement, technician visit, ticket escalation, or written next step.