extentions do detiri...deterioa..(bugger) get worse, if you have a look at the cabling and face plate forum you should see some examples.

buit the only to check is by testing from the test socket, this would rule out any internal wirirng problems
(i must say if your attenuation has gone from 13 to 33 then something major may have happened from the exchange end, but will not know untill the test, are you sure is did not say 15.5 which was a bug in the v1)