Still not hitting $500 consistently but... Wavekit https://wavekit.app/ It's an audio hosting service with high quality audio and a customizable unbranded player. Embeds are done with iframes but we're starting to offer web components which offer some cool opportunities like interaction between components. Most of our customers are selling some kind of audio product or service. Think plugin developers, sound designers, media composers, etc. Currently working on a B2B integration with an API so that it would be trivial to add audio to any web app. Think chats, marketplaces, etc.