root@rpi0w:~/gocode/src/github.com/bettercap/bettercap# airmon-ng start wlan0

Found 4 processes that could cause trouble.
Kill them using 'airmon-ng check kill' before putting
the card in monitor mode, they will interfere by changing channels
and sometimes putting the interface back in managed mode

  PID Name
  289 avahi-daemon
  301 avahi-daemon
  617 wpa_supplicant
  628 dhcpcd

PHY	Interface	Driver		Chipset

phy0	wlan0		brcmfmac	Broadcom 43430

		(mac80211 monitor mode already enabled for [phy0]wlan0 on [phy0]10)