it shouldn't affect your radio however if you do cut power then the radio it's self will rest too.
Also have you tried a few other things like making your the air filter is clear, fuel filter is new (Haynes say replace it every 2-3 yrs - depending on mileage)
i get about 85-90 out of a tenner and i have a janspeed decat and a k&n 57i. btw mines a 1ltr.