I have multiple SSIDs in my Xiaomi Mi Router 3G OpenWRT router. When I connect to the first SSID (wlan0, 2.4GHz) with my laptop (Intel Centrino Wireless-N 2230) I have strange things on system log which happen every second:
Sun Jun 16 09:54:01 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:07 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:11 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:11 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:12 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:12 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:13 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:13 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:16 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:25 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:35 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:35 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:35 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:35 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:37 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:37 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:40 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:49 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:49 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:50 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:50 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:50 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:51 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
Sun Jun 16 09:54:51 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX dynamic
Sun Jun 16 09:54:51 2019 daemon.notice hostapd: wlan0: STA-OPMODE-SMPS-MODE-CHANGED 60:36:dd:XX:XX:XX static
I don't see this when my laptop connected to other SSIDs. My other devices doesn't have this problem