ShiftPWM and Tone Problem

Hi,

Author of the library here. This error is my fault.

The library uses timer 1 by default, but I made an error in a recent update, which I corrected the next day:

You downloaded the library at just the wrong moment.

This error made the compiler complain about not having a timer3, even when it was not used.

So just update to the newest version and you will be fine.