You do not need to go through the trouble of swapping out RCA cables. The WS-420 has the aux input for an ipod already. It is the 3.5mm input. If you have the cable that is ipod jack to rca. All you need is a rca to 3.5 mm jack. You can go to radio shack and get one. And if you cannot find the female rca to male 3.5mm, They are plenty of male rca to male 3.5mm around and you just get a rca barrel to conect the rca's. This way, you radio stays on and when you want ipod. You push the button on the front of the 420 to aux.