I've never 'got'

Ah, thanks. I still don't understand the line 'I hear you singing in the wire', although the line 'I can hear you through the whine' must then refer to him eavesdropping on her conversations ...

The wind will cause the wires to "sing". The whine is just the noise powerful electric equipment often makes, most audible when you're close to it. So the imagery here is of him imagining a link to her through the natural/unnatural sounds of his everyday (and very solitary) work. It's not a creepy song.