Hi guys,

I bought a brand new TP LINK router Archer AX50 from shopee

I think receive a lemon unit or 2.4ghz band is broken or bugged
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ISP-MAXIS PLAN 100MBPS

router firmware 1.0.8 Build 20200426 rel.65338(5553)
hardware version Archer AX50 v1.0

i have 4 wifi printer 2 canon and 2 brother

4 laptop using wifi (1 lenovo, 2 asus, 1 surface) - 2 ASUS laptop couldnt connect to 2.4ghz, the others can but very unstable ping

1 AIO desktop(using wifi and only have 2.4ghz) high ping un-useable)

14 desktop using LAN (ALL NO PROBLEM)

PROBLEM 1 (MAJOR PROBLEM)
WIFI 2.4GHZ is not working but 5ghz is working seamlessly.

i have 4 wifi printer, all of them having full signal on 2.4ghz but just couldn't do their job like before, out of curiosity I try to connect my laptop via 2.4ghz and went to CMD and type "ping 192.168.1.1 -t" the result are very bad, most of the ping are above 200ms sometimes goes up to 4000ms or A LOT OF TIME OUT, speedtest result was below 10mbps or failed. when i switch back to 5ghz i get steady 2-5ms and get almost full speed from my ISP plan (100mbps).

PROBLEM 2
2 out of 4 laptop couldn't connect to 2.4ghz network , those 2 using build in wireless card QUALCOMM ATHEROS QCA9377, yes i tried to uninstall and update, still couldnt connect. They only able to connect 5ghz

I did some google for answer and saw a few post complaining about 2.4ghz and only this website have the solution 

with his setting but still fail.
"I set the RTS Threshold for both the 2.4 and 5 Ghz bands to 500, and set the beacon interval for both bands to 40. This seems to have stabilized the connection for all devices and have lasted at least the last 12 hours without losing their connection to the router. This seems to be the solution, and it's my understanding this was probably due to outside interference from another device. This seems to have solved my problem entirely, and I'll create a new thread if the issue returns."


I TRIED TO PLAY AROUND WITH THE SETTING
RESET EVERYTHING
2.4GHZ WIRELESS SETTING
SET TO SMART CONNECT