I only wish my tone charts were as level as yours. They used to be with my prior provider and ever since being with BE (A little over a year now) they have decayed into this complete and utter ugly mess...
Its only because i live close to the exchange with a nice 22db downstream attenuation that my speed is still a healthy 17000-18000kbps even on its worse day as that chart shows. Otherwise it would be a right disaster.
It still disconnects regularly no matter what BT do (including a change of tie pair since being with BE) and multiple call outs. Prior to moving to BE that was a nice level chart and the line performed perfectly (my record being over 12 months uptime without a single disconnect) with BE im beyond lucky if it stays syned for 12 days.
BE like the idiots they are say it is normal and nothing is wrong.
The other line in this house which belongs to another person is with a C&W reseller and is basically a nice level chart in DMT.
BE are just a useless provider with an unreliable product, i noticed increased latency from the day i joined BE. Sites that with my old ISP would ping in the 8-10ms range right up to the day i moved to BE on that line suddenly ping in the 20-30ms range, connection would regular drop from day one also.
I have several charts saved which show clearly how things have got worse and worse in the year ive been with BE. Its not the line either there have been 4 BT visits including one SFI visit which can not find the reason for it behaving like it does, and the charts i have saved for the 4+ years i was with my prior provider show no SNR decay and nice smooth level charts on the exact same line.
BE are just rubbish ive had more issues with them than any prior ISP. The ISP before BE i had for 4 years with NO ISSUES at all, before that i had an ISP for 2 years again NO ISSUES, no what i call connection decay.
They are just a truely dreadful ISP. Im hoping BT stick to the date this time and i get a FTTC service available at the end of march, if not ill be migrating the line to the same C&W ISP the other line here is with, and i suspect the moment i do the wonky all over the shot SNR graph will return it its normal nice level self.