Dear Community, There is a known issue affecting older RG520NEBD modem firmware versions. If you are experiencing issues with your mobile connection and your device is using an RG520NEBD modem, please check your modem firmware version. If your modem is currently running firmware version A05, pleas…

Good day. @Marija A06 is now available also for TRB501 ? Tks,

Hello, For the TRB501 specifically, A02 is the latest. RG520NEBDCR03A06M4G_A0.300.A0.300 is for RUTC50/RUTX50, etc. The reason being, the TRB501 modem firmware is built on the Quectel firmware (imagine an SDK on our devices). Regards, Matas.

Hi @Matas I paste the words from Quectel support (below) when I proposed the actual A02 you are using for TRB501. I hope you can do something at least for firmware A05. I have the files below, but of course I will do nothing without your authorization. TRB501 with A02 (Quectel modem firmware) is li…

Hello @mik , Thank you for your feedback. We apologize for any inconvenience caused and have forwarded your observations to our RnD team for further analysis. Regarding the firmware version, our developers compile the SDK provided by Quectel specifically for our devices. As @Matas mentioned, A02 is…

There is also a ticket (19345) waiting the passthrough solution.

@mik , We are aware of this topic, and the issues described here may also be related to the modem firmware. All relevant information has already been forwarded to our RnD team for further investigation. Best regards,

Dear @Marija @Matas Because the TRB501 without passthrough is unusable (before purchasing it, I even wrote to your support team to explain my passthrough needs, and they advised me to purchase the TRB501) and I understand you need time to solve this problem, may I can be sure of which RUTCxx/RUTXx…

Hello, In the grand scheme of things, we haven’t been getting that many reports of issues with passthrough or bridge modes (or mobile for that matter) when it comes to RUTC50/RUTX50 devices, though they can happen, in which case, we do provide support. As you may already be aware, there are new mod…

Hi @Matas a dedicated ticket already exists: [image] TRB501 signal instability and passthrough / bridge anomaly Issue @Zilvinas I have already filled the form. Do you need a desktop share now ? (Justinas, yesterday, has already taken the troubleshoot …

Known Issue With RG520NEBD Modem Firmware (Update Required)

Networking Solutions

mik May 22, 2026, 7:42am 12

Hi @Matas

a dedicated ticket already exists:

since 7 days

Kind regards,