I love my Job 😉
We discovered a new Feature on the DSL Lines. It is called DownStream Power Back Off, this feature was introduced in November 2007 and is currently only supported on German Telekom lines. Where as the ADSL2+ specifcation is from 2004. The Ciscos have implementet the specifcation from 2004 and today no router supports the 2007 specs. So if you are useing Cisco Hardware have a look here to see if your router supporting it.