There's obviously a fault on the alarm because it goes off every time he gets in his car and has done for the last 6 weeks or so and he goes out to work before 6am Mon-Sat and early on Sundays to play golf.
I know the civilised thing to do would be have a quiet word, but it's not like he doesn't know it's a problem and frankly I'm a bit scared of him. It's a huge 4 x4 pick up truck thing, his dog is a staff, he's covered in tattoos and yes I know I'm judging him by stereotypes because he's never been anything but pleasant to me, but I have overheard him being distinctly unpleasant to others.