Upload stopping download for the rest of the house

I have been having a problem for a long time with my uploading, every time I upload it knocks out the rest of the internet for the whole house.
I have had an engineer here who had never heard of this and all the support people we have spoken to for the past few months have been no help at all. We have begun looking at leaving the problem is so bad as I upload daily, but no one at Talk Talk has seemed to care or try and help at all. 

I have seen a very similar topic on this from just a few days ago and Talk Talk have updated the firmware on his router. Is this all that's needed? A firmware update? I have been out and bought new cables and a new network card for my PC from the advice of the engineer, also as of today completely reset my PC wiping all data.
Any help on this subject would be greatly appreciated as I'm at my wit's end with this now.

Thank you 
Carl