SInce a few days, my 2yo RB4011 is randomly rebooting.
"router rebooted without proper shutdown, probably power outage" is in the logs, but there was no power outage, voltage is looking good at 23.7v
Devices on the same power outlet are all running fine, so no dip in the lines and such. Another PSU didn't help.

I read people had it with 7,13.x firmwares, mine is running 7.14 now.
Support didn't respond for a few days, so hope someone here has any idea on how to fix or at least can confirm the behavior i'm seeing is comming from 7.13+ releases.

Got feedback from the support team, if i could also flash this version to the board (/system/routerboard/upgrade) and see if it helps.
Hope it does....

update: Nope, still random reboots...

Got advice from support to turn of SMB, this seems to be the solution, no reboots since then.

Have been having the same issue with my RB4011. Have just disabled SMB and will see if that fixes it.

For what it's worth, I have an RB4011 (the US model) too, and it's been on 7.14 for a while and now 7.14.1 and zero reboot issue here. So it's unlikely to be a hardware-wide issue in that sense or I would also be affected..
I don't use SMB, though - so yes, perhaps that's where your issue lies (especially if both of you are using it, as seems to be the case...)

If you weren't actually using SMB, perhaps try power the device from a suitable alternative/new power supply as a bad power supply is often to blame for a device that randomly reboots

Have been having the same issue with my RB4011. Have just disabled SMB and will see if that fixes it.

Router has been up for over 24-hours now with SMB turned off. Seems like it might be working. Assume if you hear nothing more from me, disabling SMB resolved the issue.

Nope, unfortunately just had another reboot. May attempt downgrading to see if that fixes it - router used to be rock solid.

Have been having the same issue with my RB4011. Have just disabled SMB and will see if that fixes it.

Router has been up for over 24-hours now with SMB turned off. Seems like it might be working. Assume if you hear nothing more from me, disabling SMB resolved the issue.

Rolled back to 7.13 and seems to work, uptime now exceeded 4 days. Used to crash every 24 hours or so.

Crashed after 5 days up on 7.13 ... less frequent but appears to still have problems. Have since rolled back to 7.12. Too early to tell if it's fixed it, has only been up for just over a day. But assume it has if I don't post an update.