Wireless • Troubleshooting

Fixed wireless playing up? Fix the common faults before you call support

Fixed wireless is a solid option where fibre has not reached, but slow speeds, dropouts and weather wobble catch most businesses out at some point. Almost every fault sits in one of a handful of places. Here is how to find yours and fix it, cheapest checks first.

Last verified 29 June 2026
By the WhichVoIP editorial team
6 min read

5 faultscover most FWA problems

4 checksyou can do yourself

Line of sightthe foundation of the link

LTE backupkeeps you online in an outage

The short answer

Why is my fixed wireless internet slow or dropping?

Most fixed wireless problems trace to one of four things: a tired or overloaded router, a blocked or misaligned outdoor antenna, peak-hour congestion on a shared tower, or weather that has shifted your equipment. Work cheapest first. Reboot and check the router, confirm the antenna still has clear line of sight and is aligned, then talk to your provider about the tower or a higher tier.

faults behind most FWA issues

checks before you call support

places a fault lives: you or the link

an LTE backup keeps you online

A Fixed Wireless Antenna Mounted On A Rooftop With A Clear View Toward A Distant Tower — Fixed wireless depends on a clear line of sight between your antenna and the operator’s tower. Most faults start here.

Start here: is it your network or the link?

Before you blame the provider, work out which side of the connection the problem is on. It saves a wasted support call and points you straight at the fix.

A fixed wireless connection has two halves. On your side sit the router, your Wi-Fi, the indoor cabling and the power feeding it all. On the other side sits the radio link: the outdoor antenna, its line of sight to the tower, and the tower’s own capacity. A quick way to tell them apart is to plug a laptop straight into the router with a cable. If the wired speed is fine but Wi-Fi is poor, the problem is your network. If the wired speed is also poor, the fault is in the router or the radio link beyond it.

The two halves of a fixed wireless connection

The five faults, cheapest fix first

Run these in order. Most businesses are back to normal by step two, and you only escalate to the provider once you have ruled out your own kit.

Reboot and check the routerPower-cycle the router and look at its status lights. An ageing or overheating unit, or one juggling too many devices, throttles everything behind it. This is the five-minute fix that solves a surprising share of complaints.

Confirm line of sightFixed wireless needs an unobstructed path to the tower. Trees grow and new buildings go up, so a link that was perfect at installation can degrade over a season. Check for anything new in the antenna’s sight line.

Check alignment after rough weatherWind and storms can nudge an antenna a few degrees, which is enough to drop speed or the connection. Inspect the mount and brackets, and ask for a re-alignment if signal strength has fallen.

Test at off-peak timesIf speeds sag only in the evenings, you are likely hitting congestion on a shared tower. Compare a midday speed test with an evening one. A consistent peak-hour dip is a capacity issue to raise with the provider.

Tidy up your Wi-FiIf wired speed is fine but Wi-Fi is weak, the radio link is healthy and the problem is in-building. Reposition the router, reduce interference, or add an access point for distant rooms.

✓

Bottom line: the wired-laptop test is your single most useful diagnostic. It tells you in two minutes whether to fix your own network or pick up the phone to the provider.

Symptom to fix, at a glance

Match what you are seeing to the most likely cause, then the first thing to try.

Symptom	Likely cause	First fix
Slow only in the evenings	Peak-hour congestion	Off-peak speed test, then call provider
Speed dropped after a storm	Antenna knocked out of alignment	Inspect mount, request re-alignment
Gradual decline over months	New obstruction in line of sight	Check for trees or new buildings
Wired fine, Wi-Fi poor	In-building Wi-Fi, not the link	Reposition router or add an access point
Frequent full dropouts	Tired router or power issue	Reboot, check the router and its power

Before you escalate, plug a laptop into the router with a cable. That one test tells you whether the fault is yours to fix or the provider’s.

WhichVoIP editorial view

A Technician Checking A Fixed Wireless Router And Signal Readings Indoors — If a wired laptop is fast but Wi-Fi is slow, the radio link is healthy and the fix is inside the building.

When to call your provider, and what to ask

Once you have ruled out your own router and Wi-Fi, the remaining faults sit with the operator. Go in with specifics so you skip the script.

Tell them what you have already tested, the wired speed figures at peak and off-peak, and when the problem started. Then ask the questions that actually move things: is there a closer or higher-capacity tower you could connect to; is your plan on shared or business-priority bandwidth; and can they re-align or upgrade the antenna. If congestion is the issue, a higher tier or a dedicated connection may be the only real fix.

⚠

Watch for: single points of failure. If your business cannot afford to be offline, add an LTE or second-line backup that fails over automatically. Redundancy is no longer a luxury for a connection your operation depends on.

Our verdict

Fixed wireless is reliable when the basics are right: a healthy router, a clear and aligned line of sight, and a tower that is not overloaded. Most faults are quick to find if you work cheapest first and use the wired-laptop test to split your network from the radio link. Escalate with evidence, and add a backup connection if downtime would genuinely hurt.

Our recommendation: run the reboot and wired-laptop test before anything else. If the link itself is the problem, raise tower capacity and antenna alignment with your provider, and price an automatic LTE failover for resilience.

Outgrowing your fixed wireless connection?

Compare business internet options in your area, from fixed wireless to fibre, matched to what your team needs.

Compare business internet
When fixed wireless beats fibre

Frequently asked questions

Why is my fixed wireless slow only in the evenings?

That pattern usually means peak-hour congestion on a shared tower. Compare a midday speed test with an evening one. If the dip is consistent, raise it with your provider and ask whether a higher tier or business-priority bandwidth is available.

How do I know if the problem is my router or the link?

Plug a laptop straight into the router with a cable and run a speed test. If the wired speed is fine but Wi-Fi is poor, the fault is your in-building network. If the wired speed is also poor, the problem is the router or the radio link beyond it.

Can weather really affect fixed wireless?

Yes. Heavy rain and cloud can briefly degrade signal, and wind or storms can nudge the antenna out of alignment, which lowers speed or drops the connection. After rough weather, check the mount and request a re-alignment if signal strength has fallen.

What is line of sight and why does it matter?

Fixed wireless needs a clear path between your antenna and the operator’s tower. Trees grow and new buildings go up, so an obstruction that appears over time can degrade a link that worked perfectly at installation. Clearing or raising the antenna often restores it.

Should I have a backup internet connection?

If downtime would hurt your operation, yes. An LTE or second-line backup that fails over automatically keeps you online when the primary link drops. For a connection your business depends on, redundancy is a sensible cost, not a luxury.

When should I switch from fixed wireless to fibre?

When fibre becomes available at your premises and you need higher, more consistent speeds or lower latency. Fixed wireless remains the better choice where fibre has not reached or where you need a quick install, so compare both for your specific address.

Keep reading

When fixed wireless beats fibre
Starlink alternatives in South Africa
Compare business internet providers

Sources: WhichVoIP editorial analysis of fixed wireless access troubleshooting; line-of-sight, antenna alignment, shared-tower congestion, QoS and LTE failover are standard networking concepts (shown as guidance, not provider claims). Verified 29 June 2026.