Okay, so I thought for fun I would try out Kali linux to do some wifi cracking and learn about hacking and experiment. I was using Kali Linux 2.1.2 ARM img and I couldnt find anyone with the same issue as I had. I cannot start monitoring mode on kali to use reaver, aircrack etc. I can connect to wifi and browse the internet, but when I use the command "airmon-ng start wlan0" it detects the interface wlan0 but says unknown driver. I cannot start monitoring mode to do anything. I updated and upgraded Kali but I cannot start monitoring mode. Can anyone tell me what's happening or how to fix it? Thank you!