AC5400X Internet Speed drop by 50% after few hours

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Hi,
I just purchased AC5400X and I am using 800Mbps from my ISP. I tested the speed through Ookla Speedtest and consistently getting 800Mbps for 1st time. However after few hours, the Speedtest dropped by 50% to 400 Mbps and I have to restart the C5400X router in order to get back 800Mbps from Speedtest.
May I know why is this happening and any solution to maintain the internet speed in long term?
Thanks
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@renatomefi this means they dont care after service. I regret giving them 2nd chqnce and purchase their product.
Previously i use to be like urs set for schedule reboot everyday but issue is aome of my devices cant establish wifi connection after reboot. I.e cctv and so on.
But now i got beta firmware from some one and is fix the issue just they disable the HomeCare feature... ie. Parentcontrol. I have to accept with this limitation no other choice since tplink dont wanna fix it.
Save some money and go asus layer.
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I have the C5400 v2 with the latest stable firmware, 1.2.5 Build 20190411 rel.52981(5553). I had to go into the QoS section of the Advanced tab on the home page of the router setting menu to manually edit the Total Bandwidth entry to 900 Mbps down and 20 Mbps up for my supposedly 600mbps Xfinity service. At the wall of the house it was around 880 and at the modem it was around 680 or so. Now, I get anywhere from 620 to 690. No beta firmware required.
There is a button on the Basic tab of the Network Map page named Speed Test. When I tested, it would register no more than 315/12 and that is what showed up automatically in the Total Bandwidth entry in both the QoS Application Priority page and Device Priority page. When I manually edited the QoS Application Priority page entry to 900/20, the bandwidth restriction to both my wired and wireless devices went away. It also automatically changed the entry in the QoS Device Priority page to match so that I didn't have to make duplicate entries.
Hope this helps...
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Thanks for the tip. I was about to pull the trigger to jump to Asus but now I guess I will sit with this problem for a little longer. Seem no solution other than keep rebooting the router. It is really sad that no one from the companies care anymore.
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The problem I have was never on the Wired devices. Seem LAN ports does get the full bandwidth when you disable the QoS. However, the same cannot be say abut the WIFI side where it keeps dropping after a few hours. In my case, no matter what setting I try to use on the QoS, nothing works on WIFI. Only reboot.
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@rickyfok3728 @Leonlay @renatomefi
Hello all, apologies for the super late reply.
It is suggested to update the Archer C5400X to the latest firmware released on the local website, which should fix this speed issue you reported.
While if it still persists and we want to try the beta first, here it is:
Note: There is guidance in the download folder and you may refer to it to update the firmware.
Do let the community know if the issue is fixed or not, thanks a lot~
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Contacted local tplink support and my issue is fix now. Need to do hard reset and flash with firmware as mention in website for the latest.
Note to taken where u run speed test from router it alway ovsrite the speed in homecare. If your speed getting slow from ur device that because the qos speed had been reduce time to time when ubdoing speed test.
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I have the latest firmware and did what you said in the qos but still getting only less than half the speeds im supposed to get. Is yours still working correctly?
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The slow speed is from LAN or Wifi? Or thr speedtest done in router apss?
Is thisnhappen in ur previous ? After reboot u get the same issue?
If after reboot ur speed remain half then i beliefe something sifferent issue from us. We get speed slow down after few hours and the speed restore every reboot.
Which package you using?
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@Leonlay my speeds going into router are what im supposed to get 600mbs but if I connect thru ethernet or wifi from the router it cuts it down to 200mbs or lower. I tried the beta firmware update and the newest update, still having the lower speeds.
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