I don't know how people end up putting all the cables down one side though? as it is easier to seperate them...
The gromet for the power cable is in the passenger footwell so makes sense to put it down the passenger side of the car... and there isn't much space in the top of the passenger footwell because of the fusebox, so running the wires from the back of the headunit (Remote cable, auxillaries) would be easier to put them down the drivers side... underneath the carpet...
Then you shouldn't have any issues with buzzing... and you don't have a massive buldge under your carpet