The sketch on your synth was compiled with Arduino 1.0.5r2 and Mozzi v1.0.2 That may seem pretty old, but boy was that build fast! This version is optimized to compile for speed, which is very important for the Mozzi sound synthesis library to run effectively. After v1.0.5 Arduino defaults to optimize for smallest compile size. Subsequent releases of Mozzi have tried to resolve this. The Mozzi github page describes some small configuration tweaks you can make to newer Arduino installs to force it to compile for speed, but we have not tested these other combinations of Mozzi and Arduino.
We discuss this in detail in the README file on our own github page. If you get Macchiato to compile and run with a different version of Arduino and/or Mozzi, PLEASE LET US KNOW!
FOLLOW UP: We released some updates summer 2017 in an attempt to rewrite the Macchiato to compile on a more recent version of Arduino and Mozzi. These updates had some stability and other performance issues, and we recently reverted to a vamped-up version of the old code. So the latest release, v1.1.2 (software file v1_171024) is packed with the latest features, sounds a little better and is every bit as stable as the original Macchiato — but it still has to be compiled with Arduino 1.0.5r2.