We just switched over to DSL from modem on home computers. Put DSL filters
on the handsets in the house and also on the cord going to the computer
modems. When we try to receive faxes only one of the computers will even
attempt to "answer" the call. Is it possible that the two middle wires that
we are using on the wires running through the house are reversed on the
non-functioning modem? Both computers could previously do this. The
suspect line can operate a telephone no problem. Seems odd to work on one,
but not the other. The junction box on the exterior of the house has red to
red and green to green, haven't yet figured out which connection goes to
which outlet. Should I randomly try reversing some wires or does it even
matter?

I need some advice about where to get and how much to pay for a prepay
mobile phone SIM in Canada.

My parents are travelling this week to visit elderly relatives and are
planning to take two mobiles but have no idea where to get SIM
cards(buying one for Canada in the UK is seriously expensive)

I have an unlocked Nokia 6230i and a 6230 phone for them which are
Triband (GSM900, 1800 and 1900 I think) so they'd need a network they
can use those mobiles on. Taking their own mobiles is prohibitively
expensive because of the roaming charges.