SNR drops and HEC erros rise dramatically when phone is in operation

[#1]

As soon as i call out or receive a call SNR drops and HEC erros rise dramatically
I am in the process of uploading a video to  vimeo.com showing the problem. As OR insist the problem is rein which I highly doubt.
I'm leaning more towards HR fault or maybe condition of the line. Ali cables are used from the CAB to the DP. CAB distance in a straight line from DP is approximately 800 Meters so line is most probably longer.

As you can guess with 4 people in my dwelling-place using the telephone at any time day/night cause's atrocious disconnections & lag and abysmal speeds.
When telephone is not in operation the broadband is remarkable with no disconnections nor is there any lag or slow downs.

Kind Regards 
BigTabs 

[#2]

Video showing the problem using telephone and router stats SNR  https://vimeo.com/91475501

[#3]

Uploading a video showing the telephone in operation and using speedtest .net will modify this when the two video's have completed
https://vimeo.com/91481245
https://vimeo.com/91481158

[#4]

Hi BigTabs,
I can see that you've got an engineer booked in to investigate and resolve this issue for you. Please do let us know how you get on.

[#5]

Engineer did not show up hopefully PlusNet will get an update why it was missed or hopefully he will still come.

[#6]

I've just been in touch with our Faults Team and we;re chasing this up and will be in touch very shortly.
Really sorry for the inconvenience caused.