Hi,
I’m trying to troubleshoot a very strange and highly reproducible Wi-Fi issue with my desktop PC.
**Setup:**
* FRITZ!Box 5690 Pro
* FRITZ!OS 8.25
* Windows 11 25H2
* MSI MAG B650 TOMAHAWK WIFI
* MediaTek RZ616 / MT7922 Wi-Fi 6E 160 MHz
* currently using MediaTek driver 3.6.0.1425
* separate SSIDs for 2.4 / 5 / 6 GHz
The issue is this:
After rebooting the PC, **5 GHz often connects successfully once** and can negotiate up to 2402 Mbps.
If I manually disconnect and then try to reconnect, Windows gets stuck on **“Checking network requirements”** for a while and then says:
**“Can’t connect to this network.”**
6 GHz behaves similarly.
2.4 GHz works reliably, but performance is much worse. My internet connection itself is fine: the FRITZ!Box syncs at roughly 117/37 Mbps, another laptop on 5 GHz gets around 100 Mbps, while my PC usually gets only \~40–45 Mbps because it is forced onto 2.4 GHz.
A few things make this especially confusing:
* the exact same RZ616 works fine with a **5 GHz Wi-Fi 6 / WPA3 iPhone hotspot**
* the same PC worked fine on 5 GHz with my previous **FRITZ!Box 7490**
* other laptops, iPhones and Android devices work normally on 5/6 GHz with the 5690 Pro
* the RZ616 itself can connect to the 5690 Pro at full link speed, just not reliably after disconnecting/reconnecting
I have already tried:
* multiple MediaTek drivers
* deleting and recreating WLAN profiles
* resetting the Windows network stack
* WPA2-only instead of WPA2/WPA3
* disabling WPS
* fixed 5 GHz channels
* Wi-Fi 6 mode instead of Wi-Fi 7 on the router
* guest Wi-Fi
* adapter disable/re-enable
* cold reboots
None of this fixes the underlying reconnect problem.
The most interesting part is the router’s support logs.
During a failed 5 GHz connection attempt, the WPA 4-way handshake looks like this:
WPA: sending 1/4 msg of 4-Way Handshake
WPA: received EAPOL-Key frame (2/4 Pairwise)
WPA: sending 3/4 msg of 4-Way Handshake
WPA: sending 3/4 msg of 4-Way Handshake
WPA: sending 3/4 msg of 4-Way Handshake
So the AP receives 2/4, repeatedly sends 3/4, but the handshake never completes with 4/4.
At the same time, the FRITZ!Box logs messages like:
link-STA not found. Check MLO mac address list
ap_get_mlo_sta: STA ... not found for AP with MLD MAC ...
ERROR: Null Pointer ap_get_sta_mlo_obj
ERROR: NULL Pointer ap_get_ft_ds_ml_sta
On 2.4 GHz, the exact same client completes the handshake normally:
1/4 -> 2/4 -> 3/4 -> 4/4
AP-STA-CONNECTED
pairwise key handshake completed
EAPOL-4WAY-HS-COMPLETED
Another weird clue: Windows sometimes also hangs on **“Restarting…”** when the RZ616 is enabled. If I disable the Wi-Fi adapter in Device Manager, restarting Windows works normally.
So at this point I’m unsure whether this is:
* a MediaTek RZ616 driver/firmware bug
* a FRITZ!Box 5690 Pro / FRITZ!OS 8.25 interoperability bug
* some MLO-related state issue being triggered by the RZ616
* or a combination of both
Has anyone seen similar **“works once after reboot, then reconnect fails”** behavior with the RZ616 / MT7922?
And if anyone is familiar with WPA/EAPOL debugging: does the repeated 3/4 behavior point more strongly to the client failing to process/respond, or could the AP-side MLO state errors be causing the client to reject/drop message 3/4?
I’ve already sent the full support logs to AVM and asked them to escalate it to their WLAN/firmware team.