Phone service is via Verizon. Stand alone DSL using a dedicated data
line is provided by a local co. One of the phone wall inserts and the
DSL wall insert share the same wall jack as there are two different
phone lines feeding in to that jack.

All three phones in the house went dead last week but the DSL modem
kept working OK. The phones were repaired by two Verizon techs today
but now the DSL doesn't work anymore. They mumbled something about
the DSL company putting the wires too close together but told us to
call a Verizon cable guy as it was beyond their area of expertise.
When the phone insert is plugged into the jack by itself that phone
works OK and I can use back up dial up to go online. When both the
phone insert and the DSL are plugged into the jack, that phone is dead
and of course I can't get online via my back up dial up.

The techs ran out of the house before I could grasp what they were
saying, but why would they tell us to get their cable guy if the
problem is in the wall jack? Would it be a better idea to get the
local ISP tech here?