dav wroteyep channels 1, 6,11 are very used in 2.4ghz wifi because they are clearly separated.... you have to switch channels or get a 5ghz network... i think this will solve your problem
5ghz is out of the question as i am using the AP as a wifi hotspot so i am forced to use 2.4ghz
i will try to move the channels up a notch to see what will happen .
Should i change the country or fiddle a bit with the power settings of the wireless ?