Espruino Wifi and SPW2430(microphone)

Is there anyway to get volume control without adding more hardware such as a digital potentiometer?

Just multiply the values in the buffer? E.mapInPlace(buffer,buffer,x=>x*0.5); should work ok.

back to my original question

You're getting an error for the line buf.set(fileBuf); but that's not in the code you've posted... Do you have other code in the file that you're not showing?

The other option is you've previously saved code to Espruino, and it's not getting reset properly before upload so when you upload the new code it's causing errors