It's been quite a while I've been building (mainly coding) a (digital) modular synthesizer with an Odroid-U3 and a Teensy 3.1, programmed in Pd and Arduino. Finally the prototype is fully functional! I've designed the circuit boards and sent them for printing, so in the near future I will finally build it.
Below you can see a short video of the prototype, and here's a link to the full code and board schematic and .brd file (eagle files) Feel free to check and experiment.