Rb911g-Pahacd, problem system rebooted because of kernel failure

Hardware MikroTik hardware general
1

hello. Have a link 27 km - RB911g-Pahacd in both sides
One or twice a daytime in my RB 911g-Pahacd have the same problem

System rebooted because of kernel failure
roter was rebooted without proper shutdown

Firmware is v 6.18

2

upgrade to 6.30.1 and try again
http://download2.mikrotik.com/routeros/6.30.1/routeros-mipsbe-6.30.1.npk

3

Ok. Will try.

4

Upgraded to 6.30.2 and solved the problem. Thanks !
Have another question Band is 5g hz only N Mcs at the AP is 10,11,12
When i set only 1 mcs for example mcs 9 - the points cannot connect ?