Client-mode: CTRL-EVENT-BEACON-LOSS

Hi,
does anybody know what could be causing these CTRL-EVENT-BEACON-LOSS notices in the log?

device is a Xiaomi mini running OpenWrt 19.07.2, r10947-65030d81f3
configured as a client using the 2.4Ghz radio, the wireless link itself should be fine:

      Mode: Client  Channel: 3 (2.422 GHz)
      Tx-Power: 20 dBm  Link Quality: 57/70
      Signal: -53 dBm  Noise: unknown
      Bit Rate: 43.3 MBit/s
      Encryption: WPA2 PSK (CCMP)
      Type: nl80211  HW Mode(s): 802.11bgn
      Hardware: [MediaTek MT7620]

(logs on the access point, also running openwrt, show nothing out of the ordinary).

burst of these can last anywhere from a couple of seconds to 5 minutes.

any help would be much appreciated.

> Thu Apr  9 20:47:40 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:47:45 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:47:49 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:47:53 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:47:56 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:47:58 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:47:59 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:48:01 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:48:02 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:48:03 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:48:05 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:48:08 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:48:09 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:48:10 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:48:16 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS
> Thu Apr  9 20:48:18 2020 daemon.notice wpa_supplicant[22034]: wlan1: CTRL-EVENT-BEACON-LOSS