Hi
Further to this, just been told by partner there are road works/traffic lights by our FTTC cabinet, and just checked on Roadworks.org and sure enough two sets of traffic lights are labelled there with work by BT laying ducting, starting yesterday. I walked past yesterday lunchtime and no one was there then, but the fluctuations started happening about an hour after I walked past.
Will walk past later and have a look. Perhaps it is a generator running the traffic light lights causing the fluctuation in SNR! From the fact it is listed as 8 metres and 1 metre of ducting, that suggests from the PCP up the road a bit, then 1 metre across the pavement to the cabinet. So perhaps more capacity being added and they need more pairs between FTTC and PCP, although I would have thought they would have put it in originally with space to spare.
Regards
Phil