[Heel n Toe]

Is there a tree branch lying on or touching any of those lines anywhere between the house and where they connect to the pole?

A little bit of wind blowing on it could make it saw back and forth across the line and cause it to resonate like a violin where it connects to the house.

Also check for branches against that gutter shown in the lower left... less of a chance of the same effect, but worth looking (along the entire length of the gutter since the resonance could transfer around a corner and make the noise send the sound through the fascia to the side of the house where the other connections are).

Good luck. Post more pix if that ain't it.