After a while reasoning, this seems not related to VPN usage and could be definitely like
http://forum.mikrotik.com/t/what-is-dropped-packets-tcp-ack-psh-on-port-1075/2800/1
So I looked for packet timeout values here http://forum.mikrotik.com/t/connection-tracking-timeout-values/77167/1
But I’m not sure if this is a good way to solve the issue.
This could explain other issues I have with detect-internet and dns queries…
Any ideas?
If there is no way to solve this, is there at least a way to selectively disable logging for just these packets ?