Nabu Casa’s Home Assistant Connect AUX-2 is an audio receiver designed to connect existing speakers or amplifiers to Home Assistant and Music Assistant. In a November 12, 2026 hands-on review, SSPAI writer 南桥北桥不是桥 found it easy to set up and reliable once playback began, while noting slower buffering and weaker performance over Wi-Fi.
The device supports Sendspin, an open-source multi-room audio protocol developed by the Open Home Foundation. At the time of the review, Sendspin had reached version 1.0 RC1, with a 1.0 release expected by the end of 2026. It uses timestamps and clock-drift calculations to synchronize playback across devices on a local network. Through Music Assistant, the reviewer says, existing AirPlay, Google Cast and Bluetooth speakers can also join a group with the AUX-2. Sendspin did not support home-theater surround formats such as Dolby at the time.
The AUX-2 has a 3.5 mm output that automatically switches between analog audio and digital optical output when an appropriate optical cable is connected. Its gigabit Ethernet port supports PoE, allowing one cable to provide both power and connectivity. USB, serial and Grove connections offer options for Home Assistant and ESPHome projects. The reviewer liked the finished enclosure but found the ports’ placement on opposite sides awkward for cable management.
With a PoE connection, the reviewer reported that Home Assistant discovered the device and completed setup in roughly half a minute. Routine configuration and firmware updates did not require ESPHome Builder, though users can take control through ESPHome for customization.
In the reviewer’s multi-device home test, playback stayed synchronized for several hours without audible drift. Starting playback, changing tracks and regrouping speakers took longer than expected, however. The review recommends Ethernet where possible: lossless FLAC streaming could stutter on a crowded 2.4 GHz Wi-Fi network. For installations without a network cable, the reviewer found that enabling the lower-bandwidth Opus codec in ESPHome improved wireless playback, while cautioning that their Opus configuration was for personal testing and noncommercial use.
The stated price was 520 yuan, or 450 yuan at launch. The article said the AUX-2 was due to reach SEEED Studio’s official stores on Chinese e-commerce platforms; it did not confirm that those listings were already live. It also identified the Home Assistant Voice Preview Edition, which has a 3.5 mm audio output and Sendspin support, and the less expensive, do-it-yourself SEEED Studio reSpeaker Lite board as alternatives for different needs.