In southern Spain, more specificly Andalusia, in some places people pronounce letter "s" as soft c/z. This happens more often in rural areas. When this happens this is called "ceceo". This also happens in some parts of Latin America. Let's see some examples, pronounced with and without ceceo:
With ceceo:
Without ceceo:
With ceceo:
Without ceceo:
With ceceo:
Without ceceo:
Ceceo is often seen socially more negative than positive.