Around a month ago I began to notice the wifi zones in our house were getting poorer - it became clear when we have teenagers sitting parked on the stairs because they can no longer get wifi on their devices in the living room. Wife also started complaining about wifi reception in the kitchen - all of which were fine before. Nothing has changed. House hasnt got any bigger! Also started to notice people getting problems connecting to the wifi. A couple of visitors unable to connect without multiple attempts, and being told that they were inputting the worng Wireless key (when they were definitely not) - As an ex BT employee myself (a number of years ago) I bounced back any claims from the family that BT was rubbish, but when it started happening to me I started to think, and started to research how others were getting on with HH6 and wifi. I am now seeing too many folks having problems with wifi on HH6 and not happy with the suggestions I am seeing being offered (such as buy a wifi extender, or invest in a third party router, and feel that there could be something up witth the HH6. I havent tried splitting channels or manually tweaking the wireless channels, as I think thats beyond the point. The point is the hub should deliver what it is meant to deliver out of the box. I am fully prepared to stick with BT as NO OTHER SUPPLIER can deliver me consistent 80Mbps download and 19Mbps upload to this location like BT Infintiy does, I just want the wifi that goes with it to work. Everything was fine until a month ago.
Can I get a replacement hub? Should I revert back to HH5? Any serious suggestions?
You have answered your own question. Wireless extenders might help but I would suggest that you either go back to the HH5 if it was working the way you wanted it to or buy a third party VDSL Modem/Router.
The HH6 can only select three of the thirteen wireless channels that are available. (not as "smart" as BT would have you believe). These three channels are the ones that do not overlap with other wireless channels but they are also the three wireless channels that every other wireless router uses. For that reason these channels often become congested with other nearby users.
If you consider how many wireless devices are being used in your house and then consider that a like number may be being used in your neighbours houses you can see how congested the three wireless channels can become.
If you use your HH5 or another router you will have access to the thirteen channels and can select one that is not congested. I use and recommend channel 13. I have never found any other user on that channel and it is never selected as a default channel by any router on the market.
has your firmware updated in last month? if so maybe a factory reset to make sure updated correctly