This bug is (most probably) related to power_save issues of the Ath9K module.
WORKAROUND: Disabling power saving mode (iw dev wlan0 set power_save off) fixed the problem. I added the following udev rule to set it right:
/etc/udev/rules.d/70-wifi-ath9k.rules
## DISABLE POWERSAVE for Atheros 9K Wireless Network Adapters ACTION=="add", SUBSYSTEM=="net", KERNEL=="wlan*" DRIVERS=="ath9k" RUN+="/sbin/iw dev %k set power_save off"
This bug is (most probably) related to power_save issues of the Ath9K module.
WORKAROUND: Disabling power saving mode (iw dev wlan0 set power_save off) fixed the problem. I added the following udev rule to set it right:
/etc/udev/ rules.d/ 70-wifi- ath9k.rules
## DISABLE POWERSAVE for Atheros 9K Wireless Network Adapters
ACTION=="add", SUBSYSTEM=="net", KERNEL=="wlan*" DRIVERS=="ath9k" RUN+="/sbin/iw dev %k set power_save off"