Alexa no longer controls aux input on Amazon Echo speakers
Amazon Echo devices will no longer allow Alexa voice commands to control playback from the 3.5mm aux input. The change affects users who previously used the feature to manage external audio sources.

Amazon has discontinued the functionality allowing Alexa voice commands to control playback and pausing from the 3.5mm aux input on older Amazon Echo speakers. The change was first reported by Ars Technica, citing a Reddit user who shared a notification received from Amazon.
A spokesperson for Amazon anonymously confirmed the change, but the company has not provided an official on-the-record statement to The Verge. The specific reasons for removing the feature have not been disclosed.
The modification appears to be limited to the audio input functionality. Reports indicate that controlling external speakers connected to an Echo Dot or other audio output functions remain unaffected.
It remains unclear how widespread the impact of this change is or when it was implemented. Users who relied on this feature for voice control of their audio setups may need to seek alternative methods for managing their sound systems.