Auto selection of channel on Thomson Speedtouch 585 v7 causes connectivity issues

This morning I switched on the laptop and couldn't connect to the internet. After rebooting the laptop, rebooting the router and checking if my PC could connect (it couldn't) I tried to bring up my router's web interface on http://{ip_of_default_gateway}, but I couldn't get to that either. My wireless connection icon in the system tray was showing a speed of just 1Mbps.

I grabbed a network cable and headed downstairs to see what was wrong, hooking up the laptop to it directly. After having a quick poke around the configuration menus, it was pretty apparent what had happened.

The Speedtouch 585 v7 is administration menu is a fairly simple affair. There's not much you can do here really, most of the really interesting stuff has to be done through telnet commands. Without many options to choose from, you really can't go too far wrong.

First, I went to Home Network > Interfaces > WLAN: Thomson. The quick way there is shown in the screenshot below.

Next, I entered the configuration menu by clicking the 'Configure' hyperlink in the top right of the screen:
In the configuration menu I could see that the router was set to automatically select the wireless channel, and that it was currently using channel 6:

Finally, I expanded the combo-box for 'Channel Selection' and selected 'Automatic', this unlocked the 'Channel', and I selected channel 11, which is a more commonly used wireless channel and one I didn't expect to give me problems:

Once I clicked 'Apply' that was it - the router required a restart to apply the new settings and once it came back up I was in e-business. It's been connected at 54 Mbps ever since.