In addition to the above - my iThings won't connect reliably to the 5Ghz on the 2926 but work fine on the 2Ghz. My MS Surface Pro struggles to connect at all to the 2926.

I too am happy to help, but I've been doing some more tests - iPhone X, iPad Pro and iPad mini 4 all on latest iOS and all in the same room connected on 5GHz to an AP902 - the iPhone reports 24M download, both iPads are around 500K - what on earth is going on?

OK I've done some more testing. Re-set the Network settings on both iPads - the iPad pro connected to the 5GHz signal from the AP902 and reported download speed of around 24M - so speed back up to "normal" from yesterday's very low but only 2 "bars" out of 3 showing for wifi signal strength. iPad mini 4 could not even "see" the 5GHz network from the AP902 so I could not connect to test the speed - and this is from about 6 feet away in the same room!

Seems there is something strange going on with the iOS devices and Draytek 5GHz. I've disabled all 5GHz and everything now connecting fine on 2.4GHz.

Just a quick update. Draytek have released a new firmware, but the release notes say it is only to address the critical security issues with almost all Draytek routers. It is obviously worth upgrading to, but it had no affect on my wireless problems. They are all still here.

Also, I've been contacted by Draytek support. After 5 days waiting, they sent me a message on how to setup a wireless network. I replied and told them I had set it up and pointed out that the issues were more serious than what they thought. After 5 more days they got back in touch and they want to test my config file. I sent it to them, but advised I have the same issues with a brand new router out of the box. A couple more emails went back and forth, and now I am waiting to hear back. I'm not feeling overly confident, but maybe if enough people contact them they might do something?

I've been fiddling some more and found the following with my system - iPhone X and iPad Pro (after re-set) will both connect to AP902 5G and 2925 5G (I've reverted to my 2925 for now) and both achieve my full download speed. iPad mini 4 (after two re-sets) will connect to AP902 5G but only downloads at 3-4 Mb, instead of 23-24Mb. However, the mini 4 will connect to my 2925 5G and download at the full 23-24Mb.

Perplexing to say the least, is it an Apple problem, a Draytek problem or some kind of hybrid problem?

I've just downloaded 3.8.9 for the 2862 from the .com site and upgraded my router. I've not had much time to test, but it looks like the wireless issues might be solved. They are certainly a lot better. I'll have to switch over from my AP-902 later to confirm everything is working again, but the test networks I enabled are alloowing me to connect and are fast and stable.

The fixes/improvements list is about 3 pages long, instead of the normal 5 or 6 items. Hopefully it addresses my other customers Virgin Media connection issue too.