Deauthenticated due to inactivity

Issue: Wifi problems with Android / iOS devices:

1. constant disconnects
2. logfile shows deauthenticated due to inactivity

Example log:

Mon Dec 25 04:43:38 2017 daemon.info hostapd: wlan0: STA 00:00:00:00:00:00 IEEE 802.11: authenticated
Mon Dec 25 04:43:38 2017 daemon.info hostapd: wlan0: STA 00:00:00:00:00:00 IEEE 802.11: associated (aid 2)
Mon Dec 25 04:43:38 2017 daemon.info hostapd: wlan0: STA 00:00:00:00:00:00 IEEE 802.11: disassociated
Mon Dec 25 04:43:39 2017 daemon.info hostapd: wlan0: STA 00:00:00:00:00:00 IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)

Root cause:

Solution: /etc/config/wireless → @ config wifi-iface → add option disassoc_low_ack '0'