Hi all currently having this router problem:

On Unifi Advance30, using dual band router TP-Link TL-WDR4300.
My 2.4ghz totally cant be used. Cant even load google although getting excellent signal. Tried on several devices already.
Ethernet speed getting 30mbps for dl. So the speed is there and spot on.
5ghz frequency also great. Getting full 30mbps on wifi when doing testspeed.

So if you were me, would u:

Send for repair and claim warranty? But end up maybe a 2-4 weeks without internet because waiting for repair and also the fact that im from melaka.

Or just buy dual band wireless usb, just use the 5ghz and live on with it?

Done some googling and found out there are actually many having problem whereby their 2.4ghz slower than 5ghz. Tried switch to different channels also with no results.

Download WiFi Analyzer on your Android device and use the app to search for the least congested channel.

Try channel 1, 6 and 11 first.

Spot on! 
Haven't faced any issues so far
When did your brother subscribed for 30Mb/s plan ?

Around 1.5 mths ago for his condo at a new residential area Setia Alam (near to Setia City Mall). Initially he subscribed the original Unifi 30 package of RM199. However upon the 1st bill (I checked his bill) he's been charged with:
1. Unifi 30 (prorated) - 20/30 X RM169
2. Unifi advance fee - RM169
3. 6% GST

It is clearly mentioned '169' on both line items. Anyone came across the same issue?

Im using unifi advance at house n 30mb biz advance at the shop. Im looking for a good router. As the one at home cant cover 2nd floor. The one at biz. Even phone is just beside. Wifi is do slow. Any recomendation ?

Strange 
Try using a 20Mhz instead of 20/40 Mhz usually that solves the problem

Download WiFi Analyzer on your Android device and use the app to search for the least congested channel.

Try channel 1, 6 and 11 first.

Im considering on upgrading to 30 mbps speed and my only concern right now is the router. The stock trg212m given by tm is sucks ball and i want to get TL-WR841ND for the replacement. Is TL-WR841ND good enough for 30 mbps or should i get a better router?

Recommend you get Asus RT-N12HP or RT-N14UHP

Oh, like that, first month HyppTV is free 
Please refer to https://forum.lowyat.net/topic/3780735

Is there a lot of difference than getting  Asus RT-N12HP or RT-N14UHP instead pf tplink TL-WR841ND

Tried change to 20mhz
Installed wifi analyzer and changed channels to 1,6,11
Tried disabling NAT
Updated firmware

Results still same. 2.4ghz totally lost. But,
What I see that my smart tv can use 2.4ghz perfectly for example youtubing. Very confusing. What does this mean?

Been lurking deeper and found tplink forum and apparently so many TL-WDR4300 owners having this problem and they suspected it a hardware issues. All symptoms same like me. Early 2-3 months everythings fine until one day the 2.4ghz band decided to collapse.

Also I read few post up mentioned about powerline. What is it do actually? We plug lan cable at one end and plug another one straight to my laptop?

Is there a lot of difference than getting  Asus RT-N12HP or RT-N14UHP instead pf tplink TL-WR841ND

Tried change to 20mhz
Installed wifi analyzer and changed channels to 1,6,11
Tried disabling NAT
Updated firmware

Results still same. 2.4ghz totally lost. But,
What I see that my smart tv can use 2.4ghz perfectly for example youtubing. Very confusing. What does this mean?

Been lurking deeper and found tplink forum and apparently so many TL-WDR4300 owners having this problem and they suspected it a hardware issues. All symptoms same like me. Early 2-3 months everythings fine until one day the 2.4ghz band decided to collapse.

Also I read few post up mentioned about powerline. What is it do actually? We plug lan cable at one end and plug another one straight to my laptop?

I see... no wonder la...
anyway, thanks for the info MyPIA!

My house, using UniFi, I apply Maxis Fibre under same house. They called and detected my house got UniFi ad. And ask me don't terminate UniFi until Maxis installed.

I said I'm not going terminate it since I want 2 internet line. They said OK, den they said Maxis only will give new router, but not modem, I know they share same modem with UniFi Modem, which is LAN Port 2.

I request I want separate modem but not allow to do so. So what can I do now?

go rent another house ... thats it

This is not solution.

Because they will have to utilize another port from the fiber distribution box which they reluctant to give an extra.

OK but I'm not sure whether the speed will be affected or not?

That BTU can support up to 2.84Gbps download and 1.42Gbps Upload. So it's much more than enough