Hi
We are using LHG,LHG XL, LHG HP from months without any problem, Recently we bought LHG AC for a test link. But we are facing Kernel reboot in LHG AC, when we are trying to change any configuration on running link.
Are we the single one facing such problems.
No You are not. I bought 4 packs LHG 5AC and after one month of trying to put it into work, I we experienced lots of problems. droping bandwidth, random timeouts, high pings. Signal is strong -35 distance is 1km.Tryed to low down TX to 14dbi to get signal about -55, nothing. Tried every ROS release candidate and nothing. I have several NetMetal devices and it works just fine. So I think the problem is ARM architecture. So I will put LHG, is in some corner and wait better times.
Hi, wondering if this issue is still continuing…any others with issues on the XL 5ac versions? thanks 
I have same problem.
Arm based LHG5AC ros 6.40.3 (fw3.43), cannot upgrade nor downgrade, cant touch wlan
whenever I disable or try to change wlan protocol it results in
sudden reboot and prints in LOG:
“kernel failure in previous boot”
tried to upload new fw and reboot it cutting power off ( by omnitik managed POE )
results no upgrade and file from file list disappears.
ordinary /sys reboot with new ros files also doesn’t upgrade and prints
kernel failure…
any1 found solution to this problem?
You are Shure you are using ARM Update file?
yes ofcourse I uploaded right architecture package to ARM device 
In the meantime I managed to find solution to this well known problem with arm devices.
in case if anyone is interested:
http://forum.mikrotik.com/t/lhg-xl-5ac-cant-upgrade-nor-touch-wlan/120756/1
as long as nv2/80211 is choosen there is no problem, but setting nstreme renders device
into dead end → kernel failure.
this is a old known problem - i think we se this first time in 2.9.xx version of ros.