I have a five-zone whole house audio system set up. I use Shairport-Sync (Apple Airplay), running on the same RPi3 as openHAB. The audio is piped through a USB sound device to a amplifier, to a splitter, then to impedance-matching volume controls at each zone.
I like the setup; the only frustration is when I want to mute audio to a specific zone. Currently, I’d need to go across the house to manually turn down the volume controls.
It occurred to me that routing the audio through DPDT relays, which were controlled by an OH-connected Arduino, would allow me to expose switchable zones that I could control through OH’s app or with the HomeKit. I already have an MQTT configured Arduino with extra pins.
Here is my question: I looked into commercial products, and found this 8-channel DPDT board. I’m pretty comfortable with electronics in general but am fairly inexperienced with audio. Before I spend the money, I wanted some input as to whether there’d be potential side effects of using this relay board in this way.
My other option is to build my own relay board. I’m comfortable with PCB design and Fritzing (looking for a good project like this to dig into Eagle). If this is the preferred route, I’d appreciate a suggested relay and perhaps a schematic for connecting it to 5v logic.