@hio77:
Thank you for the quick response. I can probably arrange for someone to get the stats for each line from our modems - may take a day or so. (I like your graphing and stat collection - may be I should aim to set that up for myself!)
RE the electrical spike issue, I'm not sure if that was measured or postulated. (this may have been from 18 months to 2 years ago when we were looking at reasons for the instability issues on Line 2, hence my reference to possible lateral line issues). FYI, both lines are in the same cable 'bundle' - the demarc is about 300 from the exchange. I think the cable bundle is a direct bury under the footpath of the main street.
I'm not sure what espm means? (I did know the techs who installed the lines and helped maintain it. This helped because after raising a fault thru the ISP, we could discuss issues. Unfortunately, they have either retired or moved on. However, I did talk directly to the new tech the other day. Unfortunately, the tech's authority to troubleshoot seems to end with plugging the line in at the port, so any potential card issues seem to lie with Assure [speculation on my part as I'm not sure about how things work within Chorus, nor am I sure about the architecture within the exchange] ). FYI. I knew of someone else with a VDSL line from the same exchange with similar line-drop issues - after months of trouble shooting it turned out to be an intermittent loose screw in a Chorus junction box and a crook port at the ISP's server's end