Silver-plated or single metal IC's?

With regard to single-ended interconnects (RCA), there seems to be two schools of thought about the merits of silver-plated copper versus single-element conductor (ie. pure silver OR copper etc).
I've been led to believe that Silver-plated cables only benefit very high frequency signals (like video), and not audio. Any opinions?
(I'm nowhere near a store that allows try before you buy, so comparisons would be tricky for me).