Do I need my own affiliate code to show ads?

To earn from product affiliate ads, yes: sign up for Amazon Associates and paste your tag into Product Affiliate Ads. On podspun.com, a blank code means no ad shows at all, so you never promote products without earning. On your own websites, a blank code falls back to Podspun's code until you add yours.

This Amazon code is unrelated to the Referral Affiliate Program, where you share a Podspun referral link and Podspun pays you when referred customers subscribe.