Tutorial RT-AC88U EOL with bugs? Here is the solution!

[PAPPL]

Seems RT-AC88U is EOL, and something is wrong with last official firmware.
When 5G Wifi is enabled many clients get connection issues.
In search of further security updates and working firmware for my wireless router i installed Asuswrt-Merlin (RT-AC88U_386.7_2.trx) and following a NVRAM reset (factory default reset in Administration settings).
Surprisingly is has all new WAN DNS settings like last ASUS firmware, but runs both Wifi-bands very well even with Smart Connect enabled (with following settings i found here somewhere deep inside the forum).

Here my Wifi settings which work perfectly fine even when playing Online-games while streaming Netflix/Prime...:

Wireless Settings:

Smart Connect Settings:

Wireless Professional 5GHz Settings:

Wireless Professional 2.4GHz Settings:

 

[OzarkEdge]

Seems RT-AC88U is EOL

This page does not list the AC88U as EOL:

End-of-life product list (asus.com)

OE

 

[PAPPL]

This is strange, there are major issues with the last firmware and no update since 03/25.

See: https://www.snbforums.com/threads/asus-rt-ac88u-revert-to-previous-firmware.78295/

 

[OzarkEdge]

This is strange, there are major issues with the last firmware and no update since 03/25.

See: https://www.snbforums.com/threads/asus-rt-ac88u-revert-to-previous-firmware.78295/

No update since 3/25 is not unusual, especially now that they are preparing to release 388 firmware.

OE

 

[Squall Leonhart]

there are no 5g issues with the latest firmware, don't assume theres an issue just because you have some.

 

[Gregory Phillips]

All of my ac88u's are dead and I don't miss them at all.

 

[boricua]

Seems RT-AC88U is EOL, and something is wrong with last official firmware.
When 5G Wifi is enabled many clients get connection issues.
In search of further security updates and working firmware for my wireless router i installed Asuswrt-Merlin (RT-AC88U_386.7_2.trx) and following a NVRAM reset (factory default reset in Administration settings).
Surprisingly is has all new WAN DNS settings like last ASUS firmware, but runs both Wifi-bands very well even with Smart Connect enabled (with following settings i found here somewhere deep inside the forum).

Here my Wifi settings which work perfectly fine even when playing Online-games while streaming Netflix/Prime...:

Wireless Settings:
View attachment 44166
Smart Connect Settings:
View attachment 44258

Wireless Professional 5GHz Settings:
View attachment 44164

Wireless Professional 2.4GHz Settings:
View attachment 44165

I got rid of smart connect when I reset my router; however, I did match your setup in Wireless Professional. I'll see if this fixes my issue as well 5 GHz clients disconnecting.

EDIT to add: I am on the stock RT-AC88U firmware 46065 (01/25/2022).