The Crickit HAT's speaker is run by a MAX98357 I2S amplifier, you can set it up by installing via our script on the next page. It will appear as an everyday audio interface once that's done.
The Crickit HAT has the ability to mute the I2S amplifier via the GPIO 16 pin on the Raspberry Pi. This is attached by default, which means you will need to actually configure GPIO 16 to use this feature. If you do not configure GPIO 16, the amplifier will likely be muted by default.
If you don't want to mess with setting up GPIO 16 and would rather have the amplifier be on by default (you probably do), then you can do so by cutting the trace on the back of the HAT as shown below.
And that's it! You should be good to go. Now you can move on to the next pages which will show you how to enable and configure the I2S audio output on the Raspberry Pi.