Broadband cuts out when phone call comes in on dodgy landline

[#1]

Hi folks, new to the community and after some help.

I'm not 100% sure what's a root of problem but every time a call comes in on landline phone the broadband cuts out last few days & most times needs router rebooted.

Also a landline problem & have reported line fault to BT for my elderly dad I as he can't can't make or receive calls last few days, line variable from noisy to silent. Line rental is to that other part of BT called BT!

He's a broadband unlimited plusnet customer on ADSL & download speed has recently dropped from around 17MBps to 5>6MBps (likely the disconnections a bit?). Have checked all wiring & tried multiple micro filters.

Wifi speeds earlier today were PING ms 40 -  DOWNLOAD Mbps 4.57 -  UPLOAD Mbps 0.32 with 25ms jitter & 1.7% packet loss

a week ago it was Ping 44, Download 17.7, Upload 0.78 with 0 jitter, 0 packet loss

Familiar to anyone? Spotted old post from 2014 with something similar .... Iain.

[#2]

Forgot to add router details, it's a Netgear DGN2200 & I tried the original Plusnet supplied Thompson TG585 v8 & fared no better, a lot slower too.

[#3]

Likely to be a high resistance fault on the line. Report the issue as a voice fault to BT and once it's fixed the broadband is likely to get better.

[#4]

But don't mention broadband to BT or they'll try to bounce it back to Plusnet.

The broadband will almost certainly be OK once the voice fault is cleared.