- seems to help in noisy env or adjacent APs+
  # iwconfig wlan0 rate 36M fixed
  # iwconfig wlan0 frag 2346
  # iwconfig wlan0 rts 2347
  # iwconfig wlan0 txpower 10
  # iwconfig wlan0 power off

- moar
  vim /etc/modprobe.d/my.conf
    options mac80211 max_probe_tries=10
    options mac80211 max_nullfunc_tries=4
    options mac80211 probe_wait_ms=1000