From Mikrotik:
To upgrade, click “Check for updates” at /system package in your RouterOS configuration interface, or head to our download page: http://www.mikrotik.com/download
What’s new in 6.34.4 (2016-Mar-24 13:13):
*) bonding – fixed crash on bonding slave release;
*) bonding – fixed mac-address disappearance after reboot in specific setups;
*) chr – fixed reboots with license and queues;
*) console – allow unknown scan-list names on wireless configuration to fix import;
*) fastpath – fixed rare kernel failure;
*) ipsec – take into account ip protocol in kernel policy matcher;
*) mac-winbox – try to aggregate packets & resend all pending packets on timeout;
*) ppp – do not crash when received multiple CBCP packets;
*) ppp – fixed crash when ppp interface gets disconnected and user gets authenticated at the same time (most probable with slow RADIUS server);
*) quickset – fixed wan interface selection on devices with SFP interfaces;
*) quickset – use 5GHz interface instead of 2GHz interface on SXT Lite5 ac;
*) rb3011 – fixed high cpu load breaks ethernet stats;
*) rb3011 – fixed link down messages;
*) romon – fixed romon discovery after romon ID change;
*) timezone – fixed reboot by watchdog when selecting timezones from the end of list;
*) userman – fixed www crash;
*) winbox – allow to show revoked & authority flags at the same time;
*) winbox – correctly recognise if there is need to report fan information under system health;
*) winbox – do not use area v2 names instead of ospf v3 area names;
*) winbox – make mac-winbox work with RB850.
