TL;DR
Nabu Casa has launched the $69 Home Assistant Connect Aux-2, a compact device that adds several ways to connect older or non-smart equipment to Home Assistant. It supports Bluetooth proxying, audio output and serial connections, and can host USB Zigbee or Z-Wave radios. Some features depend on existing integrations or software still in development.
Nabu Casa, the commercial arm of the Open Home Foundation, has launched the Home Assistant Connect Aux-2, a $69 device designed to connect a wider range of equipment to Home Assistant. Its ports and wireless radios support jobs including Bluetooth proxying, audio playback and serial control, giving users more options for bringing existing devices into a smart-home setup.
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The Aux-2 is a small box with 2.4GHz Wi-Fi, Bluetooth and Ethernet, plus USB-A, USB-C, an analog/digital audio jack, a Grove port and two RS-232 serial ports. A USB-connected Zigbee or Z-Wave radio can let users place that antenna where it gets better reception than it would beside their Home Assistant hub. The Aux-2 itself does not replace those radios; it provides a way to connect them over USB.
Its Bluetooth proxy feature can relay signals from Bluetooth devices to Home Assistant. The source reviewer tested that with Govee Bluetooth hygrometers, which appeared in Home Assistant after the Bluetooth proxy and Govee integration were enabled. The reviewer reported that the sensors stayed connected through three walls and a refrigerator, restoring temperature monitoring for a garage fridge and freezer. That is one reported installation, not a guarantee of range in every home.
The audio jack can connect an amplifier or powered speakers, while Home Assistant’s Music Assistant software can route supported music services to configured outputs. The reviewer said audio playback to in-wall speakers was working after setting up an amplifier and Music Assistant. The two serial ports offer another route for controlling or communicating with equipment such as TVs, AV receivers and solar inverters, though the reviewer had not tested serial control. Those capabilities use existing Home Assistant and ESPHome integrations; the device does not make every connected product compatible automatically.
What Can Home Assistant’s New Smart Home Multi-Tool Do?
The Aux-2 adds connection options for existing equipment. What it can do in each home depends on compatible devices, integrations and setup.
One box, several connection jobs
The Aux-2 extends Home Assistant; it is not a standalone hub.
Relay nearby sensors
A reported test connected Govee hygrometers through a Bluetooth proxy.
Place radios remotely
Connect a USB Zigbee or Z-Wave radio and position it for better reception.
Send music to speakers
Connect an amplifier or powered speakers; the reviewer played music using Music Assistant.
Connect equipment
Two ports may enable control of TVs, receivers or inverters, but the reviewer did not test this.
What it brings to a setup
- Bring compatible older or non-smart equipment into Home Assistant.
- Combine several connection jobs in one compact device.
- Confirm the intended device has a Home Assistant or ESPHome integration.
- USB Zigbee and Z-Wave radios are separate accessories.
Setup and software status
The reported setup used a browser for firmware and Wi-Fi, followed by guided ESPHome setup in Home Assistant.
Use USB-C and a browser to install firmware and enter Wi-Fi details.
Follow the interface prompts to install ESPHome and enable features.
Configure the services and devices needed for each use.
One Box, Several Connection Jobs
The Aux-2 addresses a practical problem for Home Assistant users: useful equipment may lack a direct connection to the smart-home system, or may be difficult to reach from the main hub. A Bluetooth proxy can bring nearby sensors into the system, and a remotely placed USB radio can help with Zigbee or Z-Wave coverage. Serial ports may also offer a way to interact with equipment that does not support newer smart-home protocols.
Combining these functions in one device could reduce the need to find separate adapters or repurpose a small computer for each task. That may make a flexible but hands-on platform easier to extend. The benefit still depends on the user’s devices, integrations and configuration, and the Aux-2 is an accessory rather than a complete smart-home hub.
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Built Around Home Assistant and ESPHome
The Aux-2 is based on ESPHome, an open platform for building and configuring devices using ESP boards. According to the source material, the Aux-2’s features draw on existing Home Assistant and ESPHome integrations rather than operating as a separate smart-home ecosystem. Nabu Casa is the commercial side of the Open Home Foundation, which runs Home Assistant.
Setup in the reported test began by connecting the device to a computer over USB-C, installing firmware from a browser and entering Wi-Fi details. The reviewer then moved it to a media console, connected power and completed setup in the Home Assistant interface. The interface prompted installation of ESPHome and guided the user through enabling the device’s features. Power can be supplied by USB-C or Power over Ethernet.
The source describes serial integration as developed earlier in 2026. It says Music Assistant and SendSpin, which support the audio function, remain in active development. SendSpin is described as an Open Home Foundation whole-home audio standard intended to group speakers across different protocols under some conditions. The reviewer had not managed to get that grouping working and could not tell whether the issue was configuration or the software’s development status.
Compatibility and Audio Still Developing
The launch information and hands-on account do not establish how well every serial-controlled device will work, or which specific equipment will be supported without extra configuration. The reviewer had not tested the serial ports, so examples such as TVs and solar inverters remain potential uses rather than confirmed results from that test.
Audio also has open questions. The reviewer got music playing through the connected speakers but had not configured SendSpin speaker grouping. They also wanted the Aux-2 to appear as an AirPlay or Spotify Connect target, but said they might simply need to configure those options. The source does not specify whether or when those capabilities will be available by default. Bluetooth performance, too, will vary with placement and household conditions; the reported connection through walls and a fridge reflects one setup.
More Tests Will Show Its Reach
The next useful test is whether serial control works with specific televisions, receivers, inverters and other equipment, and what configuration each requires. Further development of Music Assistant and SendSpin may clarify audio routing and cross-protocol speaker grouping. The source material does not provide a schedule for those software developments or additional Aux-2 features.
For now, prospective buyers can check whether their intended devices have Home Assistant or ESPHome integrations and whether they need a Bluetooth proxy, a remotely placed radio, audio output or serial access. The reported setup suggests the basic installation can be straightforward, but the range of what the device can do in a given home will depend on those compatibility details.
Key Questions
What is the Home Assistant Connect Aux-2?
It is a $69 multi-purpose device from Nabu Casa with Wi-Fi, Bluetooth, Ethernet, USB ports, audio output, a Grove port and two RS-232 serial ports. It extends Home Assistant’s connections; it is not a standalone smart-home hub.
Can it connect Zigbee or Z-Wave devices?
The Aux-2 can host a compatible USB Zigbee or Z-Wave radio, which can be placed away from the Home Assistant hub. The source does not say that a Zigbee or Z-Wave radio is built into the Aux-2.
Can it play music through existing speakers?
It can send audio through its jack to an amplifier or powered speakers. In the reported test, the reviewer played music to in-wall speakers using Music Assistant after connecting an amplifier and configuring the software.
Does the Aux-2 support serial control?
It has two RS-232 ports intended for connections to equipment such as TVs, AV receivers and solar inverters. The reviewer had not tested this function, so compatibility with specific devices remains unverified in the supplied account.
Is setup difficult?
The reviewer described setup as easier than expected: firmware and Wi-Fi details were added through a browser, then Home Assistant guided the ESPHome setup. Individual integrations and audio services may still require extra configuration.
Source: theverge.com
