Wireless is traditionally troublesome on Linux. The other day I transferred a lot of data over my wifi. After iwlwifi is finally stable for Intel devices using wicd, ath9k for Atheros wasn’t. It nearly passed out a couple of times leaving me with unusable connection speed.
I’m still testing if the culprit is hardware encryption or maybe power saving. For now I disabled hardware encryption with
sudo nano /etc/modprobe.d/ath9k.conf
options ath9k nohwcrypt=1
No further problems until now.