I have installed USB LTE modem. The lte1 interface was dynamically created. The modem inner ip address is 192.168.8.1
I have 20-50ms latency while pinging this IP when latency for the router where the modem is installed itself is always 1ms.
Why such a severe latency?

check traceroute, maybe you ping some other 192.168.8.1...
But be serious, USB devices connected to you should have 1ms latency, if not then try reboot it, change LAN ip inside that USB LTE device etc.
This is first info about it.

Show system resources usb print , to detect what that USB LTE device is.

Herein is the sreen with usb resources...

Sorry 192.168.8.1 is the modem itself.
The LTE1 is 192.168.8.100.. The ping is 1ms
But the modem is 40-80ms... Even from the router... Why?

12d1 14db probably say about E3131, my works proper but I re-flashing it with some mode firmware... and use it as usb1 device with ppp-out1.
I not know that E3131 (or maybe you have other USB LTE unit ? ) support a Hi.Link and be exist as lte1 interface. It's new for me.

Strange but from user perspective you can only have latest RouterOS and create a supout.rif and send it to support.
support@mikrotik.com or https://mikrotik.com/support

Mine is E8372
How much ms ping you have to the modem?
Others?

<1ms

Mine is E8372
How much ms ping you have to the modem?
Others?

Hello! I have E3372H-153 and also long pings to the modem itself. I don't know what the reason is, but I think that the matter may be that the modem's software is organized this way, which gives limited resources to processing icmp requests. Ping latency to a host does not mean that packets passing through it have the same latency. Maybe I'm soothing myself, yeah ) But it would be interesting to hear about the real reasons.

tool traceroute mikrotik.com use-dns=no
should show you a AVG ms to your router and final target.

some host can

• no answer
• have limits at answering and generate fake packet loose but in next hop have 0% then you know that one is not trust
• target can not answer at ping but you can know what is avg latency by prev hops.

Check below graphs.

Your USB modem or router (Hi.Link mode) should give you <1ms but big question is about what latency have next routers/hops ?

I like the Windows app who show you the avg and you can see who the latency inc from host to host... each next router give additional latency.

what is the fun to check some other hosts?
The proof that the modem has low icmp resourses is that the ping to the gate of mobile provider would be less then modem's ping.. but i do not have this type of picture...
So the conclusion is that modem slows the connection...

Then connect your USB unit to PC and check latency.
Next if latency
* exist only at RouterBoard then write to support@mikrotik.com or https://mikrotik.com/support
* exist in PC too, then write to support of unit, seller, search other firmware

Then connect your USB unit to PC and check latency.
Next if latency
* exist only at RouterBoard then write to support@mikrotik.com or https://mikrotik.com/support
* exist in PC too, then write to support of unit, seller, search other firmware

already done... this type of hell is only on RB ... Mine is "hap lite ac"...

Can confirm the same with my hap ac2 and an Huawei E8372h-155, the ping is non-sense if you ask me, the firmware is stock and the modem is detected as LTE interface.
Here is the ping to the modem's own IP while connected directly via USB:

I think Mikrotik needs to improve this, it's too absurd !

The modem does support Hi-link.

So yes, it's something in the kernel of Mikrotik that needs improvement, I think the USB interface is flawed.

Can someone please help with an workaround for this problem?

Here is proof also while using traceroute with Pingplotter:

The USB modem is highlighted. There are no hubs or anything in-between.

The jitter is so insane I think it's something related to USB bus.
Willing to experiment with firmware hacks to improve latency, but I most likely need to visit russian websites, anyone can point me to some good tutorial to open a more direct interface with the modem?

The wiki points that LTE interface only is supported, but I'm sure it's not updated.

I can sometimes get 2 ms so this is clearly some firmware issue, I'm running latest stable 6.48.

With the same modem directly in my PC I can't reproduce this issue.