Adding to comment 52. The frequencies of the access point are the same. In this example Channel 11. Is the networkmanager getting confused and makes it a connection to the incorrect access point? All evidence points in this direction. It explains also the wild changing of the signal strength.
A work around is to change the channel of you own access point to an unused channel. If there is one. wlan0 Scan completed : Cell 01 - Address: ::::: Channel:11 Frequency:2.462 GHz (Channel 11) Quality=70/70 Signal level=10 dBm Encryption key:on ESSID:"Zadel" Cell 04 - Address: ::::: Channel:11 Frequency:2.462 GHz (Channel 11) Quality=67/70 Signal level=-43 dBm Encryption key:off ESSID:"Sitecom -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/495981 Title: NM disconnects Wi-Fi every 2 minutes but iwconfig+dhclient and wicd don't -- ath9k To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/495981/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs