PPPoE dropping, packet loss.

Any Idea what the issue could be on my FTTC line?

CQM graphs

I've tried huawei and ECI modems. Ubiquiti Edgerouter X doing PPPoe. I've spoken to BT several times, they've struggled to find a fault.
I had an engineer out on Monday 10th who tidied up wiring and reset the DLM. Seemed to improve things for a time.
The modem doesn't appear to lose sync, but the PPPoE session drops and seem to be getting pretty bad packet loss.

Any advice on the best way of resolving the issue gratefully received.

Cheers

I'm just trying with a homehub. line speeds are usually 80/20. now getting.
Line state: Connected
Connection time: 0 days, 00:04:18
Downstream: 34.17 Mbps
Upstream: 14.64 Mbps

1. Product name: BT Home Hub
2. Serial number: +068343+NQ34209204
3. Firmware version: Software version 4.7.5.1.83.8.204.1.11 (Type A) Last updated 09/07/15
4. Board version: BT Hub 5A
5. DSL uptime: 0 days, 00:05:16
6. Data rate: 14994 / 34994
7. Maximum data rate: 25394 / 87171
8. Noise margin: 9.7 / 15.1
9. Line attenuation: 13.0 / 13.1
10. Signal attenuation: 13.0 / 13.1