Constantly Loosing Cellular Connection on Spitz x3000

I am testing it now -
Unfortunately, the upgrade process is not very reproducible, as in one case I can downgrade or upgrade, and expect different results than downgrading or upgrading to that same version again.

It appears there are a few conditions for a successful upgrade or downgrade:

  1. not inserting any SIM card into the router during the full process
  2. rebooting the router before and after the upgrade process
  3. cross your fingers and wish for good luck

Sometimes, I’ll also have to insert a sim card into one slot, find it is stuck in a “not registered” message, switch to the other slot, find it is in “not registered”, reboot the router, and repeat.
Eventually, things start working.

Anyway, after downgrading from RM520NGLAAR01A08M4G_01.202.01.202 (2024-02-01) to RM520NGLAAR03A03M4G_01.200.01.200 (2023-07-25), rebooting several times, switching sim card slots several times, “upgrading” to the same exact version one time, I’ve managed to find a fairly stable cellular connection for the past 10 minutes. Time will tell if this version (2023-07-25) will consistently deliver good results over the next few hours.

Note: I am in Japan using Docomo’s network!

I am also downgrading. I cannot say it was related to the firmware for sure, but I had a disconnect today that I never saw on the previous firmware (2023-07-25).

Welp… I can’t honestly say I have no clue what to do from here still… despite all the responses this far. I’m clueless which way and what exactly to do from here

You can first refer to this document to upgrade the module to RM520NGLAAR03A03M4G_01.200.01.200

Just literally did it again.

I will try to figure out how… that guide is contradicting though it appears that the modem version or whatever is different and I do not want to break my modem… nor does it appear to show where I download it from or where I begin to even type those commands as I don’t have terminal or Linux brought up unless you’re talking about doing it like in putty via SSH? But it’s not clear.
I’m sorry but I kind of need step-by-step guidance here. I guess my ADHD or autism’s getting in the way. I’ve done stuff like this before on Netgear mr6500 and a few other ones. But very carefully
This time it didn’t even load the internet configuration. It didn’t show any SIM card available to change it to until I rebooted the system.
Disabled Network acceleration but I can’t figure out how to disable the multi-land whatever. Whenever I select it, it just shows a bunch of different configurations for the hierarchy of lan versus cellular versus tether or whatever and I don’t understand what I’m supposed to be doing with that…
Again, it’s going to take me awhile to figure out how to do all those commands, especially with how the modems appear to be different and what you guys are recommending versus what I have versus what’s in those steps. So any further clarification would be appreciated

I’n the app under Internet above my IMEI it’s showing RM520NGLAARO1A07M4G.

Also somebody please refresh my memory the TTL the same as the HL right? Or the HL should be the same as TTL? I know my TTL for T-Mobile should be 64 or 65. It’s set to 65…
Some reason I seem to remember some script somewhere. That said 255 maybe? I apologize, my memory is kind of messed up from a heart attack I had a while back. But any recommendation for the HL to refresh my memory? I would appreciate as well. Sorry about all this and thank you

You should run AT+QGMR as an AT Command to find out exactly which modem firmware version is running.

TTL (IPv4) is 65. HL (IPv6) is 65 for T-Mobile U.S.

Thank you
Modem version is
RM520NGLAAR01 A07M4G_01.201.01.201

I’m getting conflicting information. Please confirm, if you can, which firmware version seems the most stable for TMO. Documentation for RM520NGLAAR01A08M4G_01.202.01.202 states: Integrated the patch to fix the problem of network disconnection in the case of unstable 5G network.

But it’s sounds like people are having more success with RM520NGLAAR03A03M4G_01.200.01.200

Please only vote if you have tried all these versions and have personal experiences on the TMO network in the USA.

Most stable firmware version on TMO USA

  • RM520NGLAAR01A08M4G_01.202.01.202
  • RM520NGLAAR03A03M4G_01.200.01.200
  • RM520NGLAAR01A08M4G_01.200.01.200
  • RM520NGLAAR01A07M4G_01.203.01.203
  • RM520NGLAAR01A07M4G_01.201.01.201
0 voters
1 Like

@mondokkia Have you checked the signal quality in the cellular history page? Does it show negative values and not display properly using the RM520NGLAAR03A03M4G_01.200.01.200 Firmware? That is what it did for me.

@gainestr My history looks normal enough though the signal dropped in the last 10 mins as the router changed bands

1 Like

@gainestr Checking the router again showed it switched to 5G NSA and the cell history has become spotty. Is that what you’re seeing?

Update -

After I downgraded from 2024-02-01 to 2023-07-25, I noticed disconnection issues almost immediately. The connection was relatively stable for about 10 minute increments, at first, and then became extremely unstable, to the point where I would have connection for 30 seconds and then a disconnect.

I upgraded again to 2024-02-01, this is the most stable version for me.
I tested VPN capabilities and found that these actually work fine. I also tested IPv6 and that seemed fine.
It seems like 2024-02-01 is the best bet - I’m sticking by my original post.

1 Like

Hey Goggles, I recommend upgrading to the newest version.
Are the steps here clear enough for you to run? Let me know, and if you questions, I can put together a quick guide.

1 Like

It’s switching to 5G NSA but where yours goes spotty, mine will literally lock up and freeze the router. I have to reboot the router. I’m currently trying different firmware but have not tested extensively enough yet to decide which one is best. The issues that I was having was with stock modem firmware R01A07

@Aron I really appreciate your opinion and will be updating firmware to latest release. I upgraded to R01A08 dated 07-20-23 several days ago and it was more stable than stock. But with the added patch and fix for security vulnerabilities, it only makes sense to upgrade to latest. Your help and insight is greatly appreciated!

1 Like

It’s switching to 5G NSA but where yours goes spotty, mine will literally lock up and freeze the router. I have to reboot the router. I’m currently trying different firmware but have not tested extensively enough yet to decide which one is best. The issues that I was having was with stock modem firmware. I’ll be updating firmware today and testing. I appreciate your help!

I compared both RM520NGLAAR03A03M4G_01.200.01.200 (2023-07-25) and RM520NGLAAR01A08M4G_01.202.01.202 (2024-02-01).

AT+QMBNCFG=“list” from 2023-07-25 firmware:

+QMBNCFG: "List",0,1,1,"Commercial-TMO",0x0A01050F,202303091
+QMBNCFG: "List",1,0,0,"CDMAless-Verizon",0x0A010126,202304251
+QMBNCFG: "List",2,0,0,"TEF_Spain_Commercial",0x0A010C00,202302071
+QMBNCFG: "List",3,0,0,"FirstNet",0x0A015300,202206171
+QMBNCFG: "List",4,0,0,"Rogers_Canada",0x0A014800,202303141
+QMBNCFG: "List",5,0,0,"Bell_Canada",0x0A014700,202111051
+QMBNCFG: "List",6,0,0,"Telus_Jasper_Canada",0x0A01F900,202304281
+QMBNCFG: "List",7,0,0,"Telus_Consumer_Canada",0x0A01FA00,202304281
+QMBNCFG: "List",8,0,0,"Commercial-Sprint",0x0A010204,202111051
+QMBNCFG: "List",9,0,0,"VoLTE-ATT",0x0A010335,202206171
+QMBNCFG: "List",10,0,0,"CDMAless_Private-Verizon",0x0A01FD28,202304271
+QMBNCFG: "List",11,0,0,"Swiss-Comm",0x0A010411,202304261
+QMBNCFG: "List",12,0,0,"Telia_Sweden",0x0A012400,202111051
+QMBNCFG: "List",13,0,0,"TIM_Italy_Commercial",0x0A012B00,202111051
+QMBNCFG: "List",14,0,0,"France-Commercial-Orange",0x0A010B21,202111051
+QMBNCFG: "List",15,0,0,"Commercial-DT-VOLTE",0x0A011F1F,202212061
+QMBNCFG: "List",16,0,0,"Germany-VoLTE-Vodafone",0x0A010449,202111051
+QMBNCFG: "List",17,0,0,"UK-VoLTE-Vodafone",0x0A010426,202111051
+QMBNCFG: "List",18,0,0,"Commercial-EE",0x0A01220B,202111051
+QMBNCFG: "List",19,0,0,"Optus_Australia_Commercial",0x0A014400,202111051
+QMBNCFG: "List",20,0,0,"Telstra_Australia_Commercial",0x0A010F00,202304251
+QMBNCFG: "List",21,0,0,"Commercial-LGU",0x0A012608,202111051
+QMBNCFG: "List",22,0,0,"Commercial-KT",0x0A01280B,202306271
+QMBNCFG: "List",23,0,0,"Commercial-SKT",0x0A01270A,202111051
+QMBNCFG: "List",24,0,0,"Commercial-Reliance",0x0A011B0C,202210211
+QMBNCFG: "List",25,0,0,"Commercial-SBM",0x0A011C0B,202111051
+QMBNCFG: "List",26,0,0,"Commercial-KDDI",0x0A010709,202306131
+QMBNCFG: "List",27,0,0,"Commercial-DCM",0x0A010D0D,202301051
+QMBNCFG: "List",28,0,0,"VoLTE-CU",0x0A011561,202204211
+QMBNCFG: "List",29,0,0,"VoLTE_OPNMKT_CT",0x0A0113E0,202306071
+QMBNCFG: "List",30,0,0,"Volte_OpenMkt-Commercial-CMCC",0x0A012010,202209221
+QMBNCFG: "List",31,0,0,"ROW_Commercial",0x0A010809,202306011

AT+QMBNCFG=“list” from 2024-02-01 firmware:

+QMBNCFG: "List",0,1,1,"Commercial-TMO",0x0A01050F,202303091
+QMBNCFG: "List",1,0,0,"TEF_Spain_Commercial",0x0A010C00,202302071
+QMBNCFG: "List",2,0,0,"ROW_Generic_3GPP_PTCRB_GCF",0x0A01FF09,202205261
+QMBNCFG: "List",3,0,0,"FirstNet",0x0A015300,202206171
+QMBNCFG: "List",4,0,0,"Rogers_Canada",0x0A014800,202303141
+QMBNCFG: "List",5,0,0,"Bell_Canada",0x0A014700,202111051
+QMBNCFG: "List",6,0,0,"Telus_Canada",0x0A014900,202112271
+QMBNCFG: "List",7,0,0,"Commercial-Sprint",0x0A010204,202111051
+QMBNCFG: "List",8,0,0,"VoLTE-ATT",0x0A010335,202208211
+QMBNCFG: "List",9,0,0,"CDMAless_Private-Verizon",0x0A01FD28,202305082
+QMBNCFG: "List",10,0,0,"CDMAless-Verizon",0x0A010126,202209281
+QMBNCFG: "List",11,0,0,"Telia_Sweden",0x0A012400,202111051
+QMBNCFG: "List",12,0,0,"TIM_Italy_Commercial",0x0A012B00,202111051
+QMBNCFG: "List",13,0,0,"France-Commercial-Orange",0x0A010B21,202401081
+QMBNCFG: "List",14,0,0,"Commercial-DT-VOLTE",0x0A011F1F,202206131
+QMBNCFG: "List",15,0,0,"Germany-VoLTE-Vodafone",0x0A010449,202111051
+QMBNCFG: "List",16,0,0,"UK-VoLTE-Vodafone",0x0A010426,202111051
+QMBNCFG: "List",17,0,0,"Commercial-EE",0x0A01220B,202111051
+QMBNCFG: "List",18,0,0,"Optus_Australia_Commercial",0x0A014400,202111051
+QMBNCFG: "List",19,0,0,"Telstra_Australia_Commercial",0x0A010F00,202304251
+QMBNCFG: "List",20,0,0,"Commercial-LGU",0x0A012608,202111051
+QMBNCFG: "List",21,0,0,"Commercial-KT",0x0A01280B,202308031
+QMBNCFG: "List",22,0,0,"Commercial-SKT",0x0A01270A,202111051
+QMBNCFG: "List",23,0,0,"Commercial-Reliance",0x0A011B0C,202210211
+QMBNCFG: "List",24,0,0,"Commercial-SBM",0x0A011C0B,202111051
+QMBNCFG: "List",25,0,0,"Commercial-KDDI",0x0A010709,202111051
+QMBNCFG: "List",26,0,0,"Commercial-DCM",0x0A010D0D,202208151
+QMBNCFG: "List",27,0,0,"VoLTE-CU",0x0A011561,202310181
+QMBNCFG: "List",28,0,0,"VoLTE_OPNMKT_CT",0x0A0113E0,202204211
+QMBNCFG: "List",29,0,0,"Volte_OpenMkt-Commercial-CMCC",0x0A012010,202212151
+QMBNCFG: "List",30,0,0,"ROW_Commercial",0x0A010809,202305221

It seems the 2024-02-01 firmware contains ROW_Generic_3GPP_PTCRB_GCF, which might explain why some people are experiencing better connectivity and/or more bands supported by the connected network. However, with the 2024-02-01 firmware, I do experience more disconnections where httping fails more frequently with TMO US. The 2023-07-25 seems more stable for me on TMO US as I rarely see httping failures.

Based on this, I guess the best firmware depends on which mobile internet provider you are using. For those who claim a firmware is better than the other, it will be useful to also mention who your internet provider is.

Thank you for that piece of information! I appreciate that you checked the difference in the MBN file settings for us. ROW_Generic_3GPP_PTCRB_GCF is extremely important for me because that is what I need to set as the default MBN file in order to fix WiFi calling and VPN UDP packets using TMO US. I do not believe that this is an issue with the TMHI SIM card. But I have a Business line that uses a standard micro SIM installed and it needs the above change to enable WiFi Calling.

My iPhone only picks up 1 bar from the closest TMO tower and many times it drops into SOS. With the Spitz X3000, I get three bars in 5g SA and 2 bars in 5g NSA. I have been experiencing drops though from 5g SA to 5g NSA with the router, but at least I still have connection even though it’s minimal. Doesn’t matter which firmware I use because of the distance I am from the tower, they all have issues! So, I guess I’ll live with the fact that I might have to reboot the router from time to time.

Within the PDF of the RM520NGLAAR0108M4G_01.202.01.202 firmware release, the PDF states that it has “Integrated the patch to fix the problem of network disconnection in the case of unstable 5G network.” It also states that it “Fixed the CVE-2023-33042/33043/33044 security vulnerabilities.”
Given that piece of information, I am forced to stick with the RM520NGLAAR0108M4G_01.202.01.202 firmware.

I have been running it for 24 hours and no reboots at all. It has dropped from 5g SA to 5g NSA but it was easily able to be put back to 5g SA mode by using AT commands. Please continue to report any other issues you may have. Either of these are still a better choice than the original firmware. Now I just need to figure out how to automate the router to re-scan for a 5g SA tower if it drops to 5g NSA. You would think that the router would be able to do that on its own and alway look for the best connection but apparently it doesn’t. At least mine doesn’t from this location.
Again, Thank You for all your input and time dedicated to testing this for all of us!

Also, Mine has NEVER switched bands from 5g NSA back to 5g SA. It will drop down but never jump back up. Apparently yours will jump back up.