Jamesblack1608

Hoping for help..I have a 05 Citroen c5 2.0 and the battery drains very quickly if the car isn't used for a few days at a time, I've had 3 new batteries in 6 months. I've tried lowering the suspension, not leaving the auto lights on and turning the interior light off but still have the same problem. I've also noticed if I turn the engine off and just sit in the car I can hear a clicking/buzzing coming from the boot and after exploring I think l it's coming from the wiring or wire box behind the plastic covering in the boot under the left hand boot window. By the looks of it, it's the wiring loom for the boot lock, boot interior light and 12v socket. I've unplugged it and the noise is still there. I think this is killing the battery maybe a short there but not sure. Can any help. Thanks in advance.