Auto injected context-aware ads are becoming increasingly common these days. Lots of podcast providers will use your IP or user information (if available) to select ads for your area or personal data and and they’ll splice it into your download. It almost always interrupts the flow of discussions but the ones I’ve heard are at least usually good enough to happen at the end of sentences and not mid sentence or mid word.
Correct, Backblaze is their own host and post on their blog often about their tech and processes. They’ve got a lot of good info on how they designed their server storage racks and stats on drive failures by brand etc