WiFi Issues - Advice

[ChrisLoudon]

Hi guys,

I have a relatively large restaurant (100 covers) and am having terrible wifi issues affecting both guests and staff.

As I work from site, whether it’s my laptop (Asus Zenbook 14 OLED) or my Pixel 8, Wi-Fi speed is terrible.

Connecting to the AP(s) isn’t an issue but once connected, wi-fi link speed frequently fluctuates between 800Mbits at the high end then a moment later its down at <20Mbit.  Few mins later its at 300 then down to 5….

My pipe to the outside world isn’t an issue as I have BTNet which is a high resilience leased fibre line (1000/100) and as I can be the first one in the door in the morning, interference / conflicts with other wi-fi clients seems unlikely.

The vast majority of network devices on the lan are hard wired except for 3 Ubiquity APs. 1 private AP serves the basement and shares the same SSID with another private AP on the restaurant floor. A 3^rd AP is for guest use only, also on the restaurant floor.

Connecting to either the guest or private AP results in the same behaviour.

My partners iPhone and Surface Pro have the same issues.

The only ‘fixed’ Wifi clients on the network are the 3 Ubiquity APs, a handful of tablets for kitchen / delivery controls, an iPAD at the front desk for reservations and a couple of Rational Ovens. There is a 4th AP on the network fitted by my EPos proivider that ONLY serves the credit card machines.

The only other source of potential interference could be a Casambi Smart Lighting system that has 50 devices but they are all all Bluetooth.

Advance IP scanner doesn’t show and IP conflics.

All wired devices report expected download / upload speeds.

Short of spending a night here and unplugging all the patch cables to see if there’s an offending device somewhere on the network, does anyone have any bright ideas?

I have another restaurant on the other side of the city with pretty much the same network layout and Ubiquity APs however no Casambi lighting and that unit appears to have no wifi issues.

Cheers

[OddOod]

First, I assume you've gone through and ensured everything is fully updated. If not, do that.
Which Ubi APs in particular? Have you ensured they're all fully updated?
Have you used WiFi Man to map out your network signal?
 

4 hours ago, ChrisLoudon said:

hard wired except for 3 Ubiquity APs

Are these wireless APs? That will increase range at the cost of congestion.
 

There's a lot of troubleshooting we can do, but there is always the option of last resort: nuke it and rebuild the network from scratch. As long as you set the SSID and password as the same, all the client devices should pick it up (unless you're a doofus like me and accidentally change the SSID from Tell My Wifi Love Her to Tell My Wifi I Love Her, and proceed to spend 5 hours readopting everything before noticing the typo)

[ChrisLoudon]

1 hour ago, OddOod said:

Are these wireless APs? That will increase range at the cost of congestion.

These are Wireless APs connected and powered via PoE back to the comms cabiniet that serves the main floor.

 

1 hour ago, OddOod said:

There's a lot of troubleshooting we can do, but there is always the option of last resort: nuke it and rebuild the network from scratch. As long as you set the SSID and password as the same, all the client devices should pick it up (unless you're a doofus like me and accidentally change the SSID from Tell My Wifi Love Her to Tell My Wifi I Love Her, and proceed to spend 5 hours readopting everything before noticing the typo)

Yeh, thats kinda where I'm at with it and its pretty much what my security company told me to do. I really just can't be arsed spending an eveing here yoinking cables!

 

I think I'll just need to bite the bullet, get some choons on and get cracking!

[OddOod]

2 hours ago, ChrisLoudon said:

These are Wireless APs connected and powered via PoE back to the comms cabiniet that serves the main floor.

Wait, so are they wireless or wired? If they're hardlined into a switch, I can't see why they'd be configured to have a wireless backhaul.

Also, seriously, grab Wifi Man and profile the network. It's a remarkably powerful tool

[ChrisLoudon]

14 hours ago, OddOod said:

Wait, so are they wireless or wired? If they're hardlined into a switch, I can't see why they'd be configured to have a wireless backhaul.

Sorry, maybe my terminology is wrong. They are wired APs back to a switch.

 

14 hours ago, OddOod said:

Also, seriously, grab Wifi Man and profile the network. It's a remarkably powerful tool

I'll give that a shot today, thx

[OddOod]

On 10/22/2025 at 2:00 AM, ChrisLoudon said:

They are wired APs back to a switch

Okay, good. I would describe that as "3 hardlined ubiquiti APs" because they are all wired into the network. 
 

On 10/21/2025 at 2:50 AM, ChrisLoudon said:

Connecting to either the guest or private AP results in the same behaviour

Are these actually separate APs? Or are both the private and guest networks being broadcast on the same APs?

 

On 10/21/2025 at 2:50 AM, ChrisLoudon said:

All wired devices report expected download / upload speeds.

This makes it sound like the problem is somewhere between the router and the clients. Could be a bad switch, bad cable, or bad AP, or very congested airspace.

On 10/21/2025 at 2:50 AM, ChrisLoudon said:

The only other source of potential interference could be a Casambi Smart Lighting system that has 50 devices but they are all all Bluetooth.

And this says to me it's probably congested airspace. Are there any other businesses/residences within 50m of the restaurant?
BT operates on the the 2.4Ghz frequency, same as wifi. So you have 50 devices all pinging off potentially all the time. I'm not familiar with this specific brand, but a lot of BT implementations in IoT are less than ideal. I'd be interested in seeing what happens if you were to set the APs to 5Ghz only. I'm sure this isn't a feasible solution, I believe lots of POS systems don't support 5Ghz, but it could help identify the problem. 
All that being said, wifiman should show lots of interference. If it does, you might be able to manually steer the APs (or maybe even the lights) to dedicated channels