Annex A or B

[#1]

This is a community so that's why I posed. I doubt if the vast majority of people thought I was bothering them as forums are for exchange of views and queries?

As for not taking your advice, there is so much conflicting information out there, it is a prudent step to get the correct information rather than taking one view on a forum. If everyone had leaned one way that would be different.

So sorry I didn't thank you personally but you will see I have thanked others and we all have life rather than leaving thanks on a forum.

The limited knowledge I share on forums, I do to help others not for meaningless clicking of  "thank" icons or show I opiniated I am!

[#2]

So, I've done some more research into whether it should be Annex A or Annex B. For all exchanges (Broadcom and Infineon), it should be Annex A. The only time when you should choose Annex B is when your exchange has the Ikanos chipset. 

However, if you choose Annex B for Broadcom/Infineon, Fritz!box will ignore this setting and treat it as if it was Annex A, which is why probably some have been successful with running their connection with Annex B setting.