question on DSL signal

[Wojciech Puchar]

>> 
> Check that -
>> it's not line problem but modem hardware problem or their routing problem.
> But isn't the sync going down a sign of a bad line connection?

yes it is.

i don't know what modem/router your ISP uses, but the one that polish 
telecom gives has 2 connection leds

one is titled "DSL" other i titled "Internet"

DSL lits when line connection is OK, "Internet" lights up when all routing 
is active, their pppoe tunneling they do etc. etc.

i often get situations that DSL was on but "Internet" off.