There was nothing wrong with my Asus router, just that I was adding more devices into home and wanted a later router with VLAN physical port capability.

The DrayTek was brand new couple months ago, actually it was a replacement for the first DrayTek which shipped with a cracked facia.

I have tried different channels and the auto setting. Seems I'm not the only one battling with DrayTek router.

Turned on laptop, no connection to Wi-Fi. Some nearby SSIDs appeared in the available network list but none of them mine.

Took very long time for my 2.4GHz SSIDs to appear, then my 5GHz SSIDs and finally connection to the remebered network. All the time my phone was still apparently connected to network with Internet connectivity.

What the hell is going on, really frustrating, any ideas please?

Although I have a mesh of 3 AP960c's elsewhere in the house devices near to the 2927ax (which isn't part of the mesh as outlined above) don't seem to have any problems connecting to it - e.g. there are currently 3 devices (2 iPhones amongst them) connected on 5GHz and 1 on 2.4Ghz, and they connect rapidly and without issue. (I have ax enabled)

I notice in your first post that you said you were having "almost zero" upload speed on LAN as well as wifi - just to be clear, are you saying that wired ethernet devices had near zero upload speed?

Has that been resolved, and if so what was the problem? Maybe there's a clue there, since it suggests there may be serious issues with your setup somewhere along the line?

Original problem was near zero upload speed on isolated VLAN (imitating guest Wi-Fi on a physical port) and all Wi-Fi SSIDs. Upload speed on the primary LAN port was perfect.

DrayTek logged into router and installed latest release candidate firmware, lowered the MTU (by 8 bytes), and moved the guest Wi-Fi on to separate VLAN. Upload speed seems to be fixed to this day.

Wi-Fi dropouts frequency seems to have reduced since installing latest stable firmware - maybe coincidence unless DrayTek made any changes since RC6. Obviously still an issue as multiple laptops can't see any of my SSIDs for a while and take ages to connect.

I have reinstalled the latest firmware but this time with the factory default values, and applying my configuration from scratch.

Will see how it performs.

No dropouts so far but still got poor/fluctuating signal on 5GHz less than 8 metres away on the same floor through 1 or 2 internal walls in a new-build.

Signal strength according to Windows laptop in those locations appears to fluctuate from reasonable to poor. I can see the Windows icon bars going up and down. When closer to the router the Windows icon is stable.

Draytek technical support say the 5GHz will certainly have reduced capacity, and any walls or doors or infrastructure at all will affect the signal strength. Ideal in open plan environment but will struggle in most settings unless in close range.

I've not been able to find any reports online of anyone having this little range. And certainly not had this problem with my previous Asus router. Perhaps I should have stayed loyal to Asus.