OpenBSD 6.7-current VM on vmd collectd timesync problem

Log messages from collectd installed on OpenBSD 6.7-current VM:

2020-07-30T12:42:08+00:00 192.168.20.15 collectd[75320]: Not sleeping because the next interval is 0.689 second in the past!
2020-07-30T12:42:25+00:00 192.168.20.15 collectd[75320]: Not sleeping because the next interval is 0.069 second in the past!

Setting 'Interval 5' or 10 in /etc/collectd.conf has no effect.

collectd sends UDP packets to syslog-ng on the host system anyway. And UDP packets arrive safely.

VM using NTP protocol to fine tune clock from the OpenBSD 6.7-current host, but collectd complain about clock skew in the past.

Any ideas?

Martin