Help please with dead head unit!!!!!

[FUN_TIME_FRANKY]

Help please!,

My 2006 RS4 was left in an Airpark whilst away for 2 weeks during that battery flattened, my own fault. On return to the Airpark the guy was about to start the car with a booster pack. Whilst approaching him i noticed smoking coming from the leads, the halfwit had them on the wrong way. Changed them round started the car everything seemed to be ok.

About half an hour into my journey home i decided to put on the Sat Nav, no power not even the lights coming on round the side when i put on the main car lights. Phoned the Airpark up and said that they'd caused a problem with my car because i'm assuming it's because of the booster pack, they're saying no change it should have been reported before i left so i'm up s**t creek.

The fuse on the drivers side panel beside door is'nt blown, i've taken out the head unit and the fuse at the back of the unit is'nt blown. When i turn the ignition on it sounds like the cd changer has got some kind of power going to it.

I'm hoping that the head unit is'nt knackered, if that was the case i would have thought the fuse at the back of the unit would have blown. Any help or ideas what solve this problem would be very much appreciated!!!!!

It's the RNS-E unit.

Cheers

Frank