@shaunmulligan Thanks for the links! I got it working just by calling a start.sh through my package.json like so:
"scripts": {
"preinstall": "bash deps.sh",
"start": "bash start.sh"
},
and then inside the start.sh i call the amixer and after that i start my app
#!/bin/bash
amixer cset numid=3 1
node /usr/src/app/server.js
Thanks again!