I am seeing some instability with latest modem firmware now (16121.1034.00.01.01.05)
lte1 disappears from interfaces list after 5-10 mins and it's simply gone.
In Resources however, there's still a Fibocom FG621-EA visible.
Only resolution: reboot
Observed on 7.13.3 and 7.13.4
When turning on lte logging, it looks like the modem is trying and trying (sending AT commands) but nothing happens.
But it could also be the famous 'modem boot loop' observed in the past, where people were told to RMA the box.
(I can't believe that - but read below)

I tried to downgrade modem firmware to 04 but it seems impossible.
File from here: https://upgrade.mikrotik.com/firmware/F ... 1.04/image, it says "firmware successfully flashed" but it simply stays on 05, even after reboot.
Also tried various reset commands like
"AT+reset" --> command not supported
"AT+RSTSET" --> command not supported
The only command which works is "AT+CFUN=15" but it looks like this is just a soft reset (restart) of the modem.
Somehow it is all not working like described here https://help.mikrotik.com/docs/display/ROS/LTE

Netinstalled to 7.13.4 but of course this didn't help - I just wanted to make sure and have a 'clean' device.
Default config - same issues.

I was reading on the forum somewhere that somebody solved this problem by simply upgrading to the latest BETA.
Gave it a try and upgraded 7.13.4 to 7.14.10 and voilà - indeed all okay, even overnight now.
I can't see anything in the changelogs 7.13.4 --> 7.14.10 that would (to my understanding) explain a different behavior here...

But I am willing to troubleshoot as it's just a lab device.
To start off with - how to downgrade the modem firmware from local file?
Knowledge of the local file process is there - but box doesn't take a lower version.
I wanted to re-flash 05 but it looks like a logic link like https://upgrade.mikrotik.com/firmware/F ... 1.05/image doesn't work, there's no 05 image.

Anyone?

Wow, it was not me !!
I'm seeing the exact same problems after upgrade to latest modem firmware.

I saw it happening on latest 7.14beta, so I downgraded to 7.13.3.
Still saw it there.
Then I did a complete config reset and now it's running for 10 minutes (wouldn't last 5 before !!)

I'll split this thread.

Thanks holvoetn.

I'm kinda glad to hear I'm not the only one - although it doesn't help.

Do we know where to get the 05 file or - even better - if it's possible to downgrade at all?
04 file I have, but box doesn't take it.

SUP-143353 created.

I also put in reference to this thread for support.

No clue how modem FW is to be downgraded.
LTE interface itself remains running but I see quite a bit of link down/up in log file (could be the flaky reception where it is located, I am aware of that. Will reposition the device to another place in the appt where I know it should remain stable).

Okay perfect.
I took mine home from office yesterday as well to have a location change.
Will be playing around a bit over the weekend now and if I find something, I will post it.
I doubt there will be news though as it looks like we've tried everything possible so far...

Reboot because of relocation aaaannndd ... it's there again.

07:48:59 lte,error lte1: no response for: AT E0 V1
..
07:49:19 lte,error lte1: no response for: AT E0 V1
...
07:49:39 lte,error lte1: no response for: AT E0 V1

Upgraded again from 7.13.3 to 7.14b10.
No dice.
Reboot again (to be sure routerboot was upgraded as well).

08:10:19 lte,error lte1: no response for: AT+GTCAINFO?
08:10:19 lte,info lte1 mbim: error: wdm send failed: 19

(don't mind timings w.r.t. previous loggings, it's not synchronized yet so the times are completely off)

Exactly the same here.
7.13.4, modem firmware 05, SIM without PIN and default config (no changes at all)

I'm going back and forth with support now and they suggest it has something to do with APN settings.
But it worked just before the FW upgrade ??

That would be really coincidence that 2 users each in another country experience the EXACT same problem after a FW upgrade to the modem but for BOTH their LOCAL APN settings are to blame ? At the exact same timeframe ?
Hard to believe.

Ah, just got a message that there MAY be a FW crash happening. Now I need to find a way they can get direct access to that device.

Aha - I have 4 APN's available and tested them all (IPv4/6, user/pw, cipher, ISP/manual, etc.)
Always the same issue.
Left it on default though for now.

Bring it online through eth1 and give them a lil BTH

Hmm ... was thinking about zerotier but indeed, bth makes more sense.
Let them use their own product

No idea why I got notified, but I sure am glad I didn't upgrade modem FW.

No idea why I got notified, but I sure am glad I didn't upgrade modem FW.

Because I split those first two posts from the AX Lite LTE thread.

Yeah it might be worth to wait with 05 upgrade.
04 is no problem - for this one you can go if you aren't already

You can't choose. It's always the latest, no ?

I'm sitting on 04 without any issues.

You can upgrade from file manually.


and then


That's what I tried 1mio times to downgrade from 05.
It says successfully installed but never really goes down to 04 or 03.

My idea was to re-flash 05 but I have no file for it as https://upgrade.mikrotik.com/firmware/F ... 1.05/image is emtpy

Or they took it down pending investigation ?
After all, support did mention the log messages they saw where an indication of a firmware crash.
Don't want that to go into the wild ...

Not a real problem for me. This is a lab device. I mainly use it to test and in case of emergencies when I really REALLY have no wifi around (hotspot on cell phone also remains an option).

You can upgrade from file manually.

True but most will simply use winbox (so do I).

I remember someone saying that those are patch files, we're not getting full firmware so there's no way to downgrade.
Found it viewtopic.php?t=198168#p1031333

Using Winbox it still offers 05 because Winbox is checking this URL:


But let's see what Support comes up with...

Mine is also a lab device and being used in 'emergency' situations or on holidays instead of a dodgy hotel wifi

FW downgraded again
Testing now, so far so good.

Ehhh - how did you do that???
And to what? 04?

I didn't.
Support did via Back To Home access

Yes, 04 again.

Pfffff
Can we please have an official way of doing this or a corrected 06 instead?
What to do now?

Wait.

Not my key skill but hey

Looking good so far.
Relocated the device to location with better reception.
Scheduled a script with bandwidth test over zerotier to home RB5009.
Running stable for 20 minutes already.

I will let it run overnight.

Made an error in the script. Started it again this morning, so far so good.
But the device was active all night and there were no issues seen, interface kept stable.
Therefor the issue was solved for me with the downgrade.

@TeWe: I suggest you also contact support, refer to the same SUP-ticket I made and then they should be able to solve it.

It's odd it seems we are the only 2 having this problem right now ??
Because he did not get any other problem report related to that FW upgrade.

I don't dare to try the upgrade after this

@TeWe: I suggest you also contact support, refer to the same SUP-ticket I made and then they should be able to solve it.

I did exactly that yesterday but not expecting miracles over the weekend.
SUP-143430

In the meantime I got hold of another device which is still running on its original firmware 03.
7.13.4 and running very smoothly.
'A newer version of modem firmware is available!' is being nicely promoted.
If nothing happens soonish many devices might be t***s up as soon as people start blindly upgrading...

After upgrading to version 16121.1034.00.01.01.05, I believe there's a critical bug related to the LTE interface. When I remove the SIM card, the LTE interface shows up, but once I insert the SIM card again, the LTE interface disappears.

(7.13.4, modem firmware 05, SIM without PIN and default config)

hAP ax lite LTE @ 7.14beta10 with 16121.1034.00.01.01.05 firmware, no SIM PIN as it's a known problem with this model. I used it for last 5 hours and 0 linkdowns or problems have occured.

Tried all possible procedures again with a fresh 7.14 rc1 but still no luck.
My hope was
*) modem - fixed modem firmware-upgrade (introduced in v7.14beta9);
*) lte - fixed APN authentication for FG621-EA modem;
but negative.
Modem still dead-ish.
Waiting for Support to reply on my ticket.

05 has been taken offline.


Showing 04 as latest version now.

Downloaded the 'new latest' 04 image now (exactly the same KB size as 'old' 04 before!) and flashed same way as I did 1mio times before
and it's reporting to be back on 04!!!
But errors in log are still the same and no connection (no IP, no DNS, no default route)
Sending/receiving various AT commands but no connection at all.
Testing different APN's also doesn't help.

I think I am suffering this as well... Will see if I manage to downgrade.

Support informed me yesterday they may have found the possible cause.
(it has to do with multiple APNs being defined and then FW crashing because of it)

About solution and resolving the issue for current incidents, I don't know.
I'm staying put on 04 now for a while.

For those still having this problem: try to only have 1 APN and see if that helps ?

I have the same problem with 7.13.4 and the latest firmware but I think have found the solution - 2 days of uptime without the problem.
First I create a new APN profile with the settings from the provider and in this profile uncheck Use network APN. Then select to only use IPv4 (default is Auto) and apply the newly created APN to the LTE interface.

This is not a 'solution' for me but rather a workaround.
It always has and should work nicely with "Use Network APN" - which means the default APN is being used with info or "config" from SIM card.
As of now it looks like there's some SIM's out there (mine included) which deliver a "" (empty content) as APN info and this might cause the provider to answer with nonsense = no connection possible.

I am providing remote access to my box for Support Team and we're investigating.

I agree and I'm certain they will mitigate this problem.
But for now, it might be a workaround.

I appear to have a very much the same issue on a new 2023 version of the SXT I purchased new a few weeks ago.
Interesting about having more than one APN.
I did set it up with two additional APNs apart in addition to the default.

The unit is located at my parents and it drops the connection a few times day and they simply power cycle the device to get it going again.
It always has lost the connect each morning they tell me.
An of course, doing a power cycle looses the log and I have been at a loss to know what was going on.

Signal quality and other signal indicators are quite good, so I have been very sure that has not been the issue, hence coming to the forum to seek some insight.
RSSI -70dBm
RSRP -93dBm
SINR 9dB
RSRQ -7.5dB

The SXT is on 16121.1034.00.01.01.03 modem firmware and says there is an upgrade for it, to ...04, but it is not yet upgraded to this.
The OS is up to date.

I will be interested to follow this thread and I might remove the unused APNs, as it does work fine on the default APN.
I have disabled 3g and just have lte as our 3g network is being dismantled here in Australia, and really only using B3 and B28 for this location.
I would monitor it remotely but their SIM car does not have a public IP.
Everything else about the SXT is fine as far as I am able to see.

As mentioned, a possible workaround at the moment is to configure a manual APN and use this one.
Make sure "Use Network APN" is deselcted and IPv4 only is set.
Also take care of proper credentials with corresponding encryption method.

And of course this manual APN must be activated to be used.
"3g and lte" I would always leave both enabled - no matter if really available or not.

Another workaround I have tested is to set the Netwatch monitor to some IP for example 8.8.8.8 and if ping failed set the script to disable/enable the lte1 interface.
UPDATE:
Just now I update to 7.13.5 and after the update when I check the firmware of the modem it now shows installed version 16121.1034.00.01.01.05 and strange latest version 16121.1034.00.01.01.04 - is this normal?

Yes, 05 has been taken offline until further notice.
Investigation and prep for a possible 06 still ongoing.
If 05 works fine with 7.13.5 then just leave as is and enjoy

7.14rc2 has a fix possibly related to this ?

Doesn't look like.
We need to wait for a polished version:
viewtopic.php?t=204440#p1058092