This is my first post.
I've completed Project 7, but one of the four switches produces no sound when I use the freq range in the book's code (505-515). The serial monitor showed a range of 517-519 when I pressed the switch, so I changed the max in the code to 520. This fixed the problem, but what could have caused this? Wrong resistor maybe? It looks like the correct one.
my non-educated quess would be, that the last color line on the resistor indicates the prescision of that particular resistor in +-X% from given Ohm. :)