You need to know how far you are from the telco central office which serves
your home. For DSL to work properly, maximum if about 17,000 feet.
Also, a lot depends on how many of those little in line DSL filters you installed
for the telephones. More than 3 or 4 and the line connection gets degraded.
DSL runs at about 10Mhz over your line to the telco office. Also have the telco
check your line for extra Loading Coils, Bridge Taps (which is when the wires
to your home, also go to another terminal, say a few blocks away) .. These must
be removed for DSL to work properly .. Same if the wires have a high resistance
leakage to ground or any foreign voltage on them. In my own case, I am 17K feet
from the co and the dsl was going up and down. After many checks, the issue was
resolved by installing a Whole House DSL filter at the entry point and running a
data feed from that into the dsl modem / router .. when this is done all the set dsl
filters come out .. Line has not dropped once since then (over 2 years now)
Note that I get 1800 as my download speed
You can get the whole house dsl filters here:
http://www.homephonewiring.com/splitters.html
I used this one: 649A1 Outdoor DSL Splitter .. it is an outdoor unit
that I used indoors .. local telephone repairman provided it free
after he ran tests on the dsl line.