You're right that support is difficult because unless there is a known issue, trial and error and detective work is needed.

I've opened a ticket, and sent config files over in case they offer any insight.

Since I opened the ticket it's been ok! I'm sure the issue will reoccur at some point though..

So..

Been on my own all day and the network has been perfect.

Kids (2) and wife come home, and missus starts watching Netflix on her laptop, kids on their iPads watching Youtube and the local wifi network has ground to a halt. My ping times to the router via wireless are up over 3000ms.

It appears to be a wifi bandwidth issue. My wired server pings to the router never go above 1ms.

So.. how to figure this one out... surely these APs are designed to take traffic from more than 4 users!

psykix wrote:
Been on my own all day and the network has been perfect.
Kids (2) and wife come home.....network has ground to a halt.

So clearly your wife is the problem; does her supplier have a support dept... or is it time for an upgrade ?

Your AP is dual-band, so perhaps you could put different (critical) devices on a different band (5Ghz vs. 2.4),
or apply QoS at the router to prevent specific device/apps using too much bandwidth.

If you run a speedtest when your wife is out, what do you get?

psykix wrote: So..

Been on my own all day and the network has been perfect.

Kids (2) and wife come home, and missus starts watching Netflix on her laptop, kids on their iPads watching Youtube and the local wifi network has ground to a halt. My ping times to the router via wireless are up over 3000ms.

It appears to be a wifi bandwidth issue. My wired server pings to the router never go above 1ms.

So.. how to figure this one out... surely these APs are designed to take traffic from more than 4 users!

What you're describing does specifically seem like interference, it's good that you're checking the latency to the router, that's the best way to check for that with a wireless LAN. What I would typically do is keep a ping running between an affected PC and then change channels on the AP until the latency and packet loss are acceptable.
Also, In [Wireless LAN 2.4GHz] > [Advanced Settings], try setting the channel bandwidth to 20MHz instead of 40MHz or 20/40MHz. Using two channels in the 2.4GHz band in my experience just results in more retransmissions.

You could use the new [Diagnostics] > [Interference Monitor] > [All Channels] to check for which channels are the best ones to use on 2.4GHz and 5GHz.

It's not interference. That was one of the things I checked. I did a scan and only one other 5Ghz showed up, and that transpired to be one of my own Sky TV boxes, so I disabled the wireless on it, since I use ethernet to connect them anyway.

I'm in a detached house on a corner, so don't pick up any other 5Ghz signals.

Also, I already have 2.4Ghz set to only 20Mhz.

Interference monitor shows only 1 access point with a channel utilization of 5% and a channel energy of 1%.

Before these Draytek APs, I had D-Link DAP2695 APs - I only switched because the AP902 have extra LAN ports which meant I could ditch a switch in each room, and to get the benefit of the central AP management.

I've had enough now anyway, and ordered Ubiquiti kit to replace all the Draytek stuff. I just need it to work to be honest.

I'm going to look at returning the AP902s as they just don't seem fit for purpose to me.

Thanks for all the help though! These are the only APs I've ever had any problems with, and I have had many over the years!