Hello GL.iNet Support Team,
I am writing to report a significant performance issue with USB tethering on my Beryl AX (GL-MT3000), currently running firmware v4.8.1.
Setup:
- Router: GL-MT3000 Beryl AX, firmware 4.8.1
- Phone: Xiaomi Redmi Note 12 Pro 5G (Android, USB mode set to 'Share connection via USB' / RNDIS)
- Carrier: Movistar Spain, 5G connection
- Cable: AUKEY braided USB-A to USB-C data cable
- Flow Offloading: both Software and Hardware enabled
Test results (Speedtest.net from a wired LAN client):
- Direct 5G speed on phone (baseline): ~380 Mbps down / ~12 Mbps up / 28ms ping
- USB Tethering via Beryl AX: ~4-5 Mbps down / ~10 Mbps up / 29ms ping
- WiFi Repeater 5GHz via Beryl AX: ~536 Mbps down / ~27 Mbps up / 27ms ping
As you can see, USB tethering delivers only 4-5 Mbps download, while WiFi Repeater on the same device and connection delivers 536 Mbps. The phone itself confirms the 5G connection is healthy.
Troubleshooting already performed:
- Tested multiple USB cables
- Verified USB mode is set to RNDIS/tethering (not file transfer)
- Confirmed router detects phone correctly as usb0 interface
- Enabled both Software and Hardware Flow Offloading
My question is: is this a known firmware limitation with Android USB tethering on the GL-MT3000, or could this indicate a hardware issue with the USB port? I have seen similar reports on your forum dating back to 2023 with no confirmed fix.
I would appreciate any guidance or confirmation of whether this will be addressed in an upcoming firmware release such as v4.9.
Thank you for your support.
