Cannot change soft block setting to "no" for AR9287 Wireless Network
You may be have a common issue with a clash between the acer-wmi kernel module and your Atheros driver.
Suggestion - copy and paste (line by line) the following into a terminal:
sudo modprobe -r acer-wmi
cd /etc/modprobe.d
sudo nano blacklist.conf
Then add blacklist acer-wmi
as a new line at the end of the file.
Save (Ctrl+O) and reboot.