Amps/subs installers, I need info please

[jaima]

Hi all,
I have now noticed on my X5 that some owner(s) before me must have had an Amp(s) and or sub(s) installed at one time or another and removed it/them as I see a lot of spliced wires with electrical tape around them!
Does anyone who has fitted amps and subs know which of the wires (if any) is more likely to cause battery drain if rewired wrongly ?
I have found that when pulled, the Audio/Nav fuse #72 (12v constant red/green wire in cargo area) the battery will not drain, does anyone know where that wire runs to ?
I have taken the mid system out and the glove box off to try and trace that wire but no joy so far?

Thanks for any help here!