The home hub cannot be used as a modem, so what you are doing is double NATing, which will not give Open NAT should anyone need it.
You would have been better using a TP Link VDSL Modem/router, as that would give you the same features, and would not involve double NAT.
Like the TP-Link AC1200 Wireless Dual Band VDSL/ADSL
I got round double NAT by turning my TP Link into an access point after it was showing that on Xbox. It now displays as normal and open.
I am surprised that bandwidth and QOS still worked, as that is implemented between the WAN side and the LAN side, and I would not expect it to work if you are just using it as a wireless access point.
Having the same issue, and have only noticed it appear recently (past 1-2months). Initially when reading into it I thought it was bufferbloat on my local network so bought a Netgear R7800 and flashed it with custom firmware to bring the better AQM/QOS functions to bear, to no avail.
My bandwidth isn't anywhere near saturated when gaming + streaming, and the addition of QOS on my local network without an improvement indicates the issue is likely further afield.
Tonight I have escalated my second complaint. BT have responded very poorly to my original one, they have not even accepted that there is an issue despite providing evidence therefore have escalated it.
I continue to have these problems, which is really frustrating for me as I am sure it is of all of you.
Please let me know if you have found a fix in the meantime
Unfortunately still no fix on my side. I've scored 0 my experiencied of the way they dealt with the fault which triggered a phone call. They don't seem to acknowledge that I have any issue. XXI century, 2019 - and their answer is that I can't play and watch netflix at the same time...
I wish I wasn't tied by a contract and I would be out of BT in a flash (even though I would most likely have issues with any other carrier - but at least I would be paying half the price).
Keep us posted guys
What is your bufferbloat rating without any QoS enabled? Does it improve when enabling QoS or limiting upload and download bandwidth - is it possible to implement something like CODELQ traffic shaping in your router?
After trying to make a complaint to BT I managed to get passed to an engineering team which I gave tracerts and other information about this issue and even linked him to the forums for more information. He has recently passed it onto the network team as after sending him data from my end, he reckons the issue is on BTs end. When I get more information I will let everyone know and hopefully, it will fix not only mine but everyone else's issue as well.
It affects all ISPs, so its not a BT issue.
Do a Google search for "netflix affecting ping"
There are loads of results, and some possible suggestions to reduce the effect