As I said on the post you made on GitHub, I'd be pretty sure it's baud rate - try 115200.
I'll close the GitHub issue - the forum is the best place for these sorts of questions.
@Gordon started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
As I said on the post you made on GitHub, I'd be pretty sure it's baud rate - try 115200.
I'll close the GitHub issue - the forum is the best place for these sorts of questions.