Need help finding a switched 12v source for turn-on lead. 2013 Audi A4

[Turborusty]

As the title says, I'm installing a basic add-on amp/sub to a '13 Audi A4 with the B&O system. I'm having a hell of a time finding an ignition-switched lead in the rear of the car to trigger the amp turn-on.

I previously did the same basic system in our own 2010 S5 and found a switched lead in the fuse panel on the rear passenger side. But on this A4, the entire fuse panel is hot/live all the time.

Any help would be appreciated.

Thank you!

Turborusty

[Euphonic]

There is a black wire in a harness behind the fuse box that is ignition.

[Turborusty]

Is this the fuse box behind the passenger side rear panel in the trunk?

[Euphonic]

No, it's the driver side front by the kick panel.

[Turborusty]

Ok thank you. Looks i'm running a wire up front. I appreciate your help!!