Listened to the one at the end of our street on the way home from our friends house and same there. Total silence.
Silly question, at the vents in the left-hand door? That's where the DSLAM is. Behind the right-hand door are the cable connections from the DSLAM and PSTN cab so that is (we hope) silent.
My broadband basic info/help site - www.robertos.me.uk My domains,website and mail hosting -Tsohost. Internet connection - O2 Standard.