"Why will my headphones not play audio?"に関する回答It could also be a DRM issue that prevents playback when something is plugged into the headphones jack. I can hear my Amazon Music and alerts just fine, but when I try text-to-speech or the add-on audible version of a particular audiobook, it will not play, except over the tiny Kindle Fire speaker. It worked a couple of weeks ago, but I noticed that my Fire updated itself on May 5th. I did download the same book (but not the Audible version) on a newer Kindle I got on eBay last weekend, so maybe there's a limit on the number of devices authorized. It kind of flies in the face of customer loyalty, as the authorization ought to just transfer to the current device.