Wildly fluctuating S/N margin

[zig29]

I'm pretty sure this is a problem with the outside wiring and such, but how common is it for a S/N margin to wildly fluctuate?  And what might be the usual causes?

Since a tech came by last week and did some work on the box for a different DSL issue, I've been having (at best) intermittent DSL connectivity with terrible speeds (something like 1200/200 when I normally get about 3300/850) -- and this is with the DSL modem directly plugged into the jack in the box outside the house, so it's not an inside wiring problem.  The line attenuation is excellent.  But in a matter of seconds the "Margin" reported in the transceiver statistics can go from 20 to 3 to 31 to 12 to -2…. and then the connection quits.  This happens constantly throughout the course of the day, and the connection is often lost within a minute or two -- though it's not quite as bad at night and it's worse in the afternoons.  The voice line is intermittently noisy as all heck, too.

I have a ticket in and I think a tech should be out here tomorrow.  Does anyone have experience with this, just in case it can help with a diagnosis and resolution? 

[smith6612]

In this case, it would be best to focus on the voice problem first. You're going to find the margin for it will sag during the same time the voice service is seeing problems. As you're seeing it at the NID you've already done the task of ruling out your inside wiring, so Verizon can't fault you there. Usually, when the voice service is fixed DSL service will also follow. DSL may not be perfectly fixed, but it will be much better.

Either way, the tech has the tools on him or her to find the problem quickly. They should be able to locate it and get you back up and running.