Given the issue does not show up when using ethernet points away from the broadband connection and towards a router/local wireless/driver type issue

In reply to a post by ukhardy07:

Also if you log in to My sky at www.sky.com/mysky
Hover over MySky
Under my package click Broadband usage and speed

Ethernet speeds are fine.

Ok I would Change the SSID and the password. The reason I say this is with the same SSID but different passwords, every device that's on will still try to connect - over and over, but will keep failing due to wrong password. As it tries to connect it can cause a slowdown... If a bad device tries to connect it may slow down the network, even if it's got the wrong password. Hence either turn every device off or change the SSID and password.

Ensure it's on WPA-2 still. Manually set a wireless channel of 1, 6 or 11. As DLM is running do not disconnect the router from the mains at all for the next 10 days.

As I believe the iMac is least likely to cause issues I would carry it down to the same room as the router.
Connect just this to the router.
How are the speeds wirelessly? How are they wired on the iMac? Test back to back.
The reason I say bring it down to the same room as the router is that iMac's are notorious at losing wireless speed with just 1 or 2 walls between.

If the iMac is bad wirelessly, turn it off, try another device. Again ensure it's in the same room as the router.

Introduce everything one by one, testing the speed on the same iMac located near the router each time.

Run a speedtest at www.speedtest.net

The iPhones are likely to be N (assuming iPhone 4 onwards)
iMac will be wireless N
Which HTC?
PS3's can have some strange WiFi (usually G/N but often quite poor on the older models).
The Sky wireless adapter may not be wireless N.
The Vaio could be anything (which OS is it)?

As DLM is running you will see speeds fluctuating often quite wildly for upto 10 days.

Report back

Edited by ukhardy07 (Sat 16-Nov-13 15:45:05)

I have changed the SSID and password. The only devices connected are a Sony Vaio Laptop (via ethernet) and from this on speedtest.net I get 5.37MBPS (which is what I was used to getting).

The other device I've connected (but wirelessly) is my iPhone 5. Now when I am sitting by the Router I get a speed of 5.21MBPS on the SpeedTest app. However when I go upstairs this either decreases to 0.5-1.5MBPS or just disconnects from the wireless entirely.

Tried this also on another iPhone 4S and the sameissue

iPhone wireless is very poor. This wouldn't be classified as a router issue, more a wireless range issue in my eyes.
To confirm are speeds all very good when in close range of the router?

A neighbour may have suddenly got extra wireless equipment, a new cordless phone, a new microwave, a baby monitor, a new front doorbell, a different stronger router etc. All of these could cause your wireless performance to drop. As an example your devices may have been associating with just 5Mbps wireless transmit rate before the issues (which is also low, but good enough for your already slow speed) and are now associating with 1Mbps transmit rate due to a marginal increase in interference, with the iPhones falling off entirely due to their bad WiFi signal overall.

Do you now have 2 Sky Hubs? A solution may be to buy a big length of ethernet cable (say 20m long) for around £2.50 on ebay, you can then run this cable from the existing Sky Hub, upstairs to where the signal is poor, here connect up your other Sky hub (changing just a couple of settings). This would yield a 2nd wireless signal.

It sounds to me like the issues you're having are just due to the wireless range being poor and as neighbours are relying more and more on wireless devices, interference gets worse and worse - causing issues like this.

I don't like INSSIDer as it literally only sees routers. Usually routers work nicely together, even on the same channel. I find that using the same wireless channel as my wireless door bell kills my wireless (yet INSSIDer doesn't see my doorbell). So often you end up on a worse channel which 'looks' free but isn't.

To sum up, if speeds are good in the same room as the router and through 1 or so walls, and only drop when you move away from the router it indicates a signal issue. Having a 2nd WiFi router is a good idea, how does this sound bearing in mind you can use the Sky Hub. Only downside is a cable between the two (hopefully can hide).
This would work http://www.ebay.co.uk/itm/20M-Meter-CAT5e-5-RJ45-Eth...

Edited by ukhardy07 (Sat 16-Nov-13 16:47:28)