2704n wont change wifi channel

[#1]

Just got a new 2704n router.  It was set to automatically choose a channel and when I checked using a WiFi analyzer, it was on channel 11.  This conflicts with a signal from one of my neighbours' wifi networks, so I changed it in the Advanced Settings to channel 6.  I tried rebooting the router twice and although the settings page says it's on channel 6, the WiFi analyzer app still showed it on channel 11.

Then I tried powering it off and back on and it changed - but only to channel 1 which also conflicts with an equally strong signal from a different neighbour.

Any advice on how to get it to change to the channel I want it to be on (channel 6)?

[#2]

fwiw, I've never used a 2704n, but if 300 mbps mode (HT40, 40MHz) is enabled, it can cause similar symptoms you describe on other routers I've used.

[#3]

Thanks Bill, that fixed it! As soon as I changed to 144 mbps mode and restarted, the channel changed to 6.

So, do you (or does anyone) know if there are any other advantages/disadvantages to using 300 mpbs?

[#4]

300mbps can in theory offer higher wireless speeds but it uses twice as many wifi channels as 144 mbps mode.

Intentionally using 300mbps mode in a congested wifi neighbourhood is not recommended.  This is more likely to be an issue on 2.4 GHz band where wifi signals travel further and basically cause interference.  The firmware in newer routers should automatically switch down to 'neighbour friendly' 144mbps mode anyway, but some routers have a 'Greenfield' mode to deliberately override this behaviour.

This is less of a problem on 5 GHz band where wifi signals don't travel as far.  Hence the proliferation of AC wireless routers which can in theory hog all the popular 5 GHz wireless channels.