Stick it in a working game that also uses one. Gottlieb Pinballs. Midway Gorf, Wizard of Wor. Qbert.
To save on buying a really expensive chip that might not be bad, you may need to send yours to a trusted friend for testing.
Otherwise, you might have to shotgun every other chip related to sending the SC-01 the speech data (assumes every other sound related thing functions properly.)