Hi,
I have a Mikrotik Cloud series router connected with 1Gb fibre to my ISP, and I have a second Routerboard on which I created another subnet. Each router does DHCP for its own subnet, and the RB is uses the Cloud as its default router. The RB is running routeros 7.5 and the Cloud routeros 6.44.6.
Ping and traceroute show <1ms latency between the RB and the Cloud on both ipv4 and ipv6, however when trying to connect with real traffic the Cloud is contacting test-ipv6 over ipv4 in 3ms, but the RB has a latency of 7 whole seconds on ipv4. Web browsing is painfully slow and imap keeps timing out. Wreshark is only telling me that there is no response and a lot of retransmits yet, but ICMP is super fast. Both RB and Cloud use the same DNS.
If traceroute is showing no latency, and wireshark doesn't help, what's the next step in troubleshooting?