I'm no expert, but I was suffering with intermittent connection on my T4U too. I was suffering outages every 45-60 seconds upon connection. 

The process mentioned below is something I have tried and fiddled with and seem to be getting a consistent level of connection with acceptable download speeds. Go to 

Device Manager > network adapters > (right click your device) > properties > advanced. Scroll down to WiFi config, set the value to WiFi (mine was set to performance). One below should be wireless mode, I have that set to auto. 

I've also gone to the power management tab on there and unchecked "allow the computer to turn off this device to save power". 

So far so good for me, coming from the person who took the dongle and hurled it across the room before I fiddled with the settings. 

If you are using a laptop, make sure your power plan isn't messing with USB power at any point as that appears to be a culprit too. 

Best 

Jake

bear729 wrote

worst product to buy damn thing disconnects on 5ghz or i get slow speeds fix ur damn drivers your drivers are 2 years old whne do u plan on fixing them windows 10 drivers needs updateing

@bear729 yea man this T4U v2 is pure trash, tp link should take responsible to get us replaced.

@JerryLoh98 

JerryLoh98 wrote

@bear729 yea man this T4U v2 is pure trash, tp link should take responsible to get us replaced.

Windows 10 appears to enforce it's own (unreliable) driver instead of using the TP-Link provided driver, and this is what is causing the adapter to disconnect from 5GHz networks.

The solution provided at https://community.tp-link.com/en/home/forum/topic/153227?replyId=506056 resolved the issue for me.

@bear729 

Model AC1300 T4U V3

I had the same problem, and the TP manufacturer changed the device, but the same problem occurred.
Of course, the driver used both the TP official version and Windows default, and the result was the same.
The peculiar thing is that the wireless connector(AX1500) also became stuck as the connection of T4U was cut off when accessing a specific web site, but the exact cause could not be found at that time.

This problem disappeared automatically after upgrading Windows 10 build from v1909 to 20H2, and there was no additional interruption.
Currently, the T4U installation driver uses the Windows built-in type, and the TP driver is not installed separately.

I think it has to do with the wireless bandwidth channel width that T4U is using, and I think it has to do with setting the wireless channel width of the 5Ghz repeater to 40Mhz to reduce the interference of the Logitech wireless keyboard (2.4Ghz), but I was wrong.

Simply put, after upgrading Windows, the T4U's Channel Width was forcibly set to 20Mhz, and the problem seems to have been resolved.

Upgrade Windows build to v20H2 or higher, and change the T4U driver to Windows one. (It will set Wireless Channel Width to 20Mhz)

Hope it works