Hello
I am fighting with problem for over months and see no solution. Tried everything which came to my mind.
Problem happens once for 3 days or 2 weeks.
Tried few RouterOS release
Simply all ports simultaneously start go down and up repeatedly
CRS works as switch only - no routing or queueing at all.
Reboot solves the problem for some time.
Below: info/error/warning/critical log.
I have no new idea

Sep/27/2018 20:38:28 interface,info ether4_IN_router link down
Sep/27/2018 20:38:28 interface,info 01ether8_kl.1 link down
Sep/27/2018 20:38:28 interface,info 13ether10_kl.13 link down
Sep/27/2018 20:38:28 interface,info 08ether11_kl.8 link down
Sep/27/2018 20:38:28 interface,info 07ether13_kl.7 link down
Sep/27/2018 20:38:28 interface,info 03ether15_kl.3 link down
Sep/27/2018 20:38:28 interface,info 02ether17_kl.2 link down
Sep/27/2018 20:38:28 interface,info 12ether18_kl.12 link down
Sep/27/2018 20:38:28 interface,info 05ether19_kl.5 link down
Sep/27/2018 20:38:28 interface,info 10ether20_kl.10 link down
Sep/27/2018 20:38:28 interface,info 04ether21_kl.4 link down
Sep/27/2018 20:38:28 interface,info 09ether22_kl.9 link down
Sep/27/2018 20:38:28 interface,info 06ether23_kl.6 link down
Sep/27/2018 20:38:28 interface,info 11ether24_kl.11 link down
Sep/27/2018 20:38:30 interface,info ether4_IN_router link up (speed 1G, full duplex)
Sep/27/2018 20:38:30 interface,info 08ether11_kl.8 link up (speed 1G, full duplex)
Sep/27/2018 20:38:30 interface,info 12ether18_kl.12 link up (speed 1G, full duplex)
Sep/27/2018 20:38:30 interface,info 05ether19_kl.5 link up (speed 1G, full duplex)
Sep/27/2018 20:38:30 interface,info 09ether22_kl.9 link up (speed 1G, full duplex)
Sep/27/2018 20:38:30 interface,info 11ether24_kl.11 link up (speed 1G, full duplex)
Sep/27/2018 20:38:31 interface,info 01ether8_kl.1 link up (speed 1G, full duplex)
Sep/27/2018 20:38:31 interface,info 13ether10_kl.13 link up (speed 1G, full duplex)
Sep/27/2018 20:38:31 interface,info 07ether13_kl.7 link up (speed 1G, full duplex)
Sep/27/2018 20:38:31 interface,info 03ether15_kl.3 link up (speed 1G, full duplex)
Sep/27/2018 20:38:31 interface,info 02ether17_kl.2 link up (speed 1G, full duplex)
Sep/27/2018 20:38:31 interface,info 10ether20_kl.10 link up (speed 1G, full duplex)
Sep/27/2018 20:38:31 interface,info 04ether21_kl.4 link up (speed 1G, full duplex)
Sep/27/2018 20:38:32 interface,info 06ether23_kl.6 link up (speed 1G, full duplex)
Sep/27/2018 20:38:54 interface,info ether4_IN_router link down
Sep/27/2018 20:38:54 interface,info 01ether8_kl.1 link down
Sep/27/2018 20:38:54 interface,info 13ether10_kl.13 link down
Sep/27/2018 20:38:54 interface,info 08ether11_kl.8 link down
Sep/27/2018 20:38:54 interface,info 07ether13_kl.7 link down
Sep/27/2018 20:38:54 interface,info 03ether15_kl.3 link down
Sep/27/2018 20:38:54 interface,info 02ether17_kl.2 link down
Sep/27/2018 20:38:54 interface,info 12ether18_kl.12 link down
Sep/27/2018 20:38:54 interface,info 05ether19_kl.5 link down
Sep/27/2018 20:38:54 interface,info 10ether20_kl.10 link down
Sep/27/2018 20:38:54 interface,info 04ether21_kl.4 link down
Sep/27/2018 20:38:54 interface,info 09ether22_kl.9 link down
Sep/27/2018 20:38:54 interface,info 06ether23_kl.6 link down
Sep/27/2018 20:38:54 interface,info 11ether24_kl.11 link down
Sep/27/2018 20:38:56 interface,info ether4_IN_router link up (speed 1G, full duplex)
Sep/27/2018 20:38:56 interface,info 08ether11_kl.8 link up (speed 1G, full duplex)
Sep/27/2018 20:38:56 interface,info 12ether18_kl.12 link up (speed 1G, full duplex)
Sep/27/2018 20:38:56 interface,info 05ether19_kl.5 link up (speed 1G, full duplex)
Sep/27/2018 20:38:56 interface,info 09ether22_kl.9 link up (speed 1G, full duplex)
Sep/27/2018 20:38:56 interface,info 11ether24_kl.11 link up (speed 1G, full duplex)
Sep/27/2018 20:38:57 interface,info 01ether8_kl.1 link up (speed 1G, full duplex)
Sep/27/2018 20:38:57 interface,info 13ether10_kl.13 link up (speed 1G, full duplex)
Sep/27/2018 20:38:57 interface,info 07ether13_kl.7 link up (speed 1G, full duplex)
Sep/27/2018 20:38:57 interface,info 03ether15_kl.3 link up (speed 1G, full duplex)
Sep/27/2018 20:38:57 interface,info 02ether17_kl.2 link up (speed 1G, full duplex)
Sep/27/2018 20:38:57 interface,info 10ether20_kl.10 link up (speed 1G, full duplex)
Sep/27/2018 20:38:57 interface,info 04ether21_kl.4 link up (speed 1G, full duplex)
Sep/27/2018 20:38:57 interface,info 06ether23_kl.6 link up (speed 1G, full duplex)
Sep/27/2018 20:39:23 interface,info ether4_IN_router link down
Sep/27/2018 20:39:23 interface,info 01ether8_kl.1 link down
Sep/27/2018 20:39:23 interface,info 13ether10_kl.13 link down
Sep/27/2018 20:39:23 interface,info 08ether11_kl.8 link down
Sep/27/2018 20:39:23 interface,info 07ether13_kl.7 link down
Sep/27/2018 20:39:23 interface,info 03ether15_kl.3 link down
Sep/27/2018 20:39:23 interface,info 02ether17_kl.2 link down
Sep/27/2018 20:39:23 interface,info 12ether18_kl.12 link down
Sep/27/2018 20:39:23 interface,info 05ether19_kl.5 link down
Sep/27/2018 20:39:23 interface,info 10ether20_kl.10 link down
Sep/27/2018 20:39:23 interface,info 04ether21_kl.4 link down
Sep/27/2018 20:39:23 interface,info 09ether22_kl.9 link down
Sep/27/2018 20:39:23 interface,info 06ether23_kl.6 link down
Sep/27/2018 20:39:23 interface,info 11ether24_kl.11 link down
Sep/27/2018 20:39:25 interface,info ether4_IN_router link up (speed 1G, full duplex)
Sep/27/2018 20:39:25 interface,info 12ether18_kl.12 link up (speed 1G, full duplex)
Sep/27/2018 20:39:25 interface,info 05ether19_kl.5 link up (speed 1G, full duplex)
Sep/27/2018 20:39:25 interface,info 09ether22_kl.9 link up (speed 1G, full duplex)
Sep/27/2018 20:39:25 interface,info 11ether24_kl.11 link up (speed 1G, full duplex)
Sep/27/2018 20:39:26 interface,info 01ether8_kl.1 link up (speed 1G, full duplex)
Sep/27/2018 20:39:26 interface,info 13ether10_kl.13 link up (speed 1G, full duplex)
Sep/27/2018 20:39:26 interface,info 07ether13_kl.7 link up (speed 1G, full duplex)
Sep/27/2018 20:39:26 interface,info 03ether15_kl.3 link up (speed 1G, full duplex)
Sep/27/2018 20:39:26 interface,info 02ether17_kl.2 link up (speed 1G, full duplex)
Sep/27/2018 20:39:26 interface,info 10ether20_kl.10 link up (speed 1G, full duplex)
Sep/27/2018 20:39:26 interface,info 04ether21_kl.4 link up (speed 1G, full duplex)
Sep/27/2018 20:39:26 interface,info 06ether23_kl.6 link up (speed 1G, full duplex)
Sep/27/2018 20:39:27 interface,info 08ether11_kl.8 link up (speed 1G, full duplex)

I see the same problem. Mikrotik is "working" on the solution but really don't reply so hurry up and wait and maybe Mikrotik will get it fixed via firmware? My RB3011 has the same issue so I removed ALL connections into reduced ALL connections down to 2 ports and moved everything into the switch. The RB3011 has not flapped but the switch does.................not sure what else works but time will tell.