Model & Firmware:

• Hardware Version: Archer BE805 v1.20

• Firmware Version: 1.3.0 Build 20250710 rel.60037(5347)

ISP Speed: 3 Gbps up / 3 Gbps down

Issue Description:
When using speedtest on my WiFi 6 devices (tested right beside the router), I initially get around 1700 Mbps down / 1600 Mbps up. However, after a few hours of uptime, the 5GHz band speed drops to about 700+ Mbps down / 1200+ Mbps up.

• The issue persists across different WiFi 6 devices.

• Restarting the client devices does not restore speed.

• Only rebooting the router restores normal speeds (1700/1600).

• The 6GHz band is not affected at all.

Troubleshooting Done:

• Verified on multiple BE805 units, same issue.

• Issue only happens when MLO (Multi-Link Operation) is enabled.

• With MLO disabled, both 5GHz and 6GHz bands are stable and achieve full speeds consistently for over a week without degradation.

Conclusion:
The speed drop appears to be linked to MLO on the 5GHz band. With MLO off, the router works fine.

Can TP-Link support confirm if this is a known firmware issue, and if there’s a fix or upcoming update planned?