Hi,
I got the same error for some time. Im my case the syslog setting in the tasmota device was the problem:
The Syslog logging was switched to something > 0 and no host was given.
So every message went to 0.0.0.0 I suppose.
Setting it to 0, i.e. no logging, and the messages went away.
The following debugging might help if this does not solve your issue:
tcpdump -i eth0 host XXX.XXX.XXX.XXX
The following was logged: IP XXX.XXX.XXX.XXX.55246 > 0.0.0.0.syslog: SYSLOG local0.info
Regards