/bin/sh: speaker-test: not found
Relax please...
speaker-test is not found because it's not installed, plain and simple.
Better to show you how to resolve this situation quickly, as it will help later.
First open APPS > go to Provides > and enter speaker-test
Note: the provides function is listed in the Search drop-down menu
"Provides" indicates in which extension you can find the desired application.
I think these details are explained in the CoreBook, yes?