Any one more of these options may not be ideally compatible with the connection that you have to your ISP's equipment.
Your Hardware and Firmware choice has to be compatible with your ISP's Hardware and there Firmware and also the modem codes.
What works for one Draytek owner may not work for another even though they may appear to be connecting to the internet via identical services.
You might have a BT line but you could be connected to for example Virgin or Talktalk for your broadband or fibre.
I would recommend that you download all the available options in advance, install the BT firmware first, if it works great. If it doesn't try disabling Hardware Acceleration. If that worked great. If not then work your way through the firmware options one at a time until you find the one that best suits your connection.
People forget that your router has to communicate with your ISP's router at the other end, both have to be compatible with each other from a hardware point of view and firmware point of view too. The routers modem codes have to be compatible with each other too.
In the same way that end users (Us, we you) have an endless choice of routers to choose from on the market your ISP also have several choices too to choose from. They are not using the same equipment and they have regular firmware upgrades to do as well from time to time.
