ESP8266 Community Forum

I haven't really played around with the hardware side of things, so this is mostly new to me but I've been mulling this project, and i'm really hoping it's trivial to do. I have an audio source that's basically always on with a bluetooth transmitter attached. There's a receiver in another room. If I disconnect the receiver, the transmitter tries to reconnect and the receiver won't stay disconnected.

My thought... Can I use a NodeMCU board to create a wifi based audio switch using just the GPIO pins? ON or OFF would be via a MQTT topic (or physical button). I would have an input audio jack connected up to 2 pins (left/right stereo), and an output audio jack connected on another 2 pins, with grounds connected. When, ON, the audio is just passed straight through the board. Audio would be at line level, so no huge voltages to deal with. No volume level adjustment or anything fancy. Just OFF, or ON/Passthrough. Is this something doable without using relays?

it should be possible with the CD405(1|2|3) type multiplexer ...

Another possibility would be to use a I2C audio preprocessor (e.g. TDA 8424) attached to the ESP which would give you mute, volume control, and bass, treble if you wanted that.

Nothing fancy. Just a simple on/off. Like if there is a way to just connect an audio signal into D1 and output to D2. -- just use it as a passthrough?

Sure, I can do it via a Mux, but just asking about the NodeMCU board itself, and if possible what would that code look like?