I've got two access points / WiFi networks at my home and there is a strange behavior with my Android 4.0 phone (SGS2): after my phone connects to one network or the other (whichever is currently stronger), the other network becomes invisible. It cannot be found in this list of currently available networks in the system menu, it is not visible in apps like Wifi Analyzer etc.
After I turn off the WiFi and turn it on again, both networks are visible again. Then I connect to one of them and after a while, the same repeats again - the other network becomes completely invisible.
What could be causing this? It is a problem for me because apps like Best WiFi then cannot work properly.