I use this in about ten devices (one of which is a custom-built dog feeder) and love it. I hate using closed-source IoT devices and this is a perfect alternative.
My site is at https://www.stavros.io/ and various smaller projects at https://www.makerfol.io/stavros/. The particular dog feeder is mostly my dad's build, I only provided the software and relays to trigger it, so it's not written up anywhere. I can post some photos if you like.
You better not hook up to the amplifier. There's a slight possibility for overload.
https://www.youtube.com/watch?v=WjX1jU9pQeY