I tried but was using at 30M cable lengths and the transceivers weren’t stable, I ended up switching to 80M transceivers and they’re solid as a rock - just ticked over 2 weeks up time with no issues. It would just be nice if we could get some proper release firmware now.
Using RC6 and RC12 the SFP+ with an S+RJ10 module I get a huge packet loss to the rest of the network.
I have a server connected via an SFP+ DAC cable at 10g without issues, so, for me, it seems to affect any speed with the 10GBase-T SFP+, did not test 10G or 5G, because of the lack of 10G NIC’s for BaseT.
I’m running 2.13rc12 on a CSS610, trunked via SFP+1 to a CRS317 at 10GbE via a DAC.
VLANs are configured and working on the 1Gb copper ports; I get correct DHCP addresses when plugging a client in.
But when I plug a client into SFP+2, regardless of how I have VLANs set up, the CSS610 will not pass traffic to SFP+2, and the copper ports also stop working properly until I re-plug SFP+1 trunk.
What is happening here? It would be great to be able to use the second SFP+ port for a 10Gb-capable client.
I am, but only over 7 MTR length to my server; so I cant vouch for range 
Can someone from Mikrotik support please explain why we have to dig through months long threads just to see if there is a new version available? Why are you avoiding putting up a pinned item for easier tracking like someone trying to avoid COVID?
This whole new set of switches and SwOS Lite seem to be the bastard children which will never get the support they deserve. Put a huge black eye on Mikrotik for me and wanting to avoid the products in the future.
Bit harsh but I get where you’re coming from - even with Covid etc etc…, not having a release software version for hardware that shipped months ago is pretty shoddy. I think MikroTik are expecting quite a lot from their customers - hardware many be cheap but if the software doesn’t work then that cheap hardware looks like an expensive paperweight.
It is more about transparency. When I first received the CCS610-8G-2S+ and powered it up, it show something like “SwitchOS 2.12” in the web UI so I went to the site, like I do for every new piece of hardware that I get, to see if there was any newer version of the code. I was really baffled as on the download page there was version 2.13 available but none of the versions included the switch I. had just purchased. I had to come to the forums and search and dig only to find out that the firmware was still in RC status and was a “Lite” version at that. I then had to search through this long a$$ post and found RC5 which I downloaded, only to find out later, in this same thread, that RC12 was available which fixed some of my issues.
It is just frustrating to get a new device in only to find out it is still in Beta, although not advertised that way, and has so many issues with very little response from the manufacturer.
I have upgraded our switch to RC12. I have two customers attached to it via ether1 and ether2 - both have GPEN powered devices on their end. The uplink to the switch is into SFP+1 using a 1G SFP module.
What we notice is on RC12, every hour at exactly :13 past the hour, the switch (and all customers behind it) loose exactly 15 pings (1 second apart) - or 15 seconds on connectivity. On RC6, we would loose access to the switch over SFP+ port so it was too unstable to use.
I have swapped out the GPEN power supplies and the SFP module. The switch at the other end of the fiber never looses a ping so the problem is in the CSS610 and seems to be in the SFP+ port. We’ve tried turning off flow control with no effect.
Looks like Watchdog is broken in RC12. This seems to be what was causing our router to reboot every 3600 seconds. I’ve turned Watchdog off and we have gone 2 hours now without a reboot.
Appearently this is RC25 haven’t checked link yet https://box.mikrotik.com/f/a4b001debcee4a05aec2/?dl=1
Edit: Yep it is
That firmware is not for the netPower 7R.
Working fine so far for me on the CSS610-8G-2S+
We need a version for the CSS610-1Gi-7R-2S+ switch.
I take back what I said about RC25 being fine, I am getting hourly reboots of the switch on the hour with full outage.
Started a transfer just before reboot for testing, you can see where the switch cuts out
Disappointing 
Interesting - mine works without issues - simple setup with ports 1-7 serving as untagged ports bound to a VLAN, 8 and both SFPs as trunk ports:
I have yet to test another issue that was present in rc12 - hotplugging (or unplugging) a SFP module from SFP2 would sometimes cause the traffic to be no longer forwarded via SFP1 (which is set as trunk port), need to re-check that though.
So far this firmware seems to be stable…
Rc25 fixes all my remaining problems
2.13rc25 breaks IGMP Snooping for me…
When IGMP Snooping is enabled in System and web interface is on the IGMP tab, multicast members are shown for a few seconds before the page is replaced with an error message in red text:
Have your device actually rebooted? Because it might be that Uptime is only bugged.
I noticed it back in RC2 with Zabbix SNMP scan. Yet I did not recall losing connection at all, i had my always plugged via the switch.
I used switched as it is in current situation usable - as dumb switch.
See my comments a little higher up. I think watchdog is broken. Our was rebooting exactly every hour as well. It was a true reboot with 15 seconds of packet loss through the switch each time it rebooted.