Amd64-hassio-supervisor is spamming mqtt server

Hi all,
I saw in my mqtt logs “Mosquitto broker” the following:

2024-06-14 17:24:41: New connection from 172.30.32.2:41938 on port 1883.
2024-06-14 17:24:41: Client <unknown> closed its connection.
2024-06-14 17:26:41: New connection from 172.30.32.2:59792 on port 1883.
2024-06-14 17:26:41: Client <unknown> closed its connection.

this repeats every 2 minutes. I checked the source IP and it belong to the amd64-hassio-supervisor conatiner. What could cause this?

After some tcpdump I have the feeling I wasted time and this is the watchdog?

yes, correct