Tried again...

it's not Power Levels.

Tried a huge bunch of devices, all of which work with V1.3.4.1 - none will connect on 5GHz, using V1.3.5.

The Windows laptops did connect - but failed to obtain an IP address via DHCP. The various cryptic messages on the other devices infer that was their problem too.

Reported to Draytek. 25/11/20

I am now connected on 5GHz using V1.3.5RC5 supplied by DrayTek support. I think I'm a guinea pig!

hornbyp wrote:
Tried a huge bunch of devices, all of which work with V1.3.4.1 - none will connect on 5GHz, using V1.3.5.

It turns out the the other key piece of the puzzle, is the use of tagged VLANs - remove those and the problem goes away.

I have just run into what looks like the same bug. I was moving and reconfiguring an AP802 from being a range extender to a normal AP. At the same time I upgraded the firmware from 1.3.3 to 1.3.5. All went to plan initially, but clients could not connect to the 5GHz. No IP address was received by various clients. Downgrade to 1.3.4.1 and it works.

I reported it to Draytek on 26th November 2020

Draytek wrote: Your query has been received and has been allocated a ticket reference of [#DQ584939].

I sent them the config. from my AP802 and instructions on how to reproduce the fault. The last response I had (same day) was:

I will need to test this out in the lab to see if I can recreate the issue. I will let you know when I have more information

Since then - nothing