Marcus Tullius Cicero was a Roman lawyer, philosopher, rhetorician and statesman who lived from 3 January 106 BC to 7 December 43 BC. Cicero is often considered as Rome's leading orator and writer of prose and had a huge influence on the Latin language.
The correct pronunciation of Cicero in Latin is with a hard "c"; therefore it is pronounced KIH-keh-roh. Cicero is often also pronounced as CHIH-cheh-roh or SIH-seh-roh. The reason for these differing pronunciations is because of the different varieties of Latin used. In Classical Latin, the "c" was pronounced with a hard "c", thus a "k" sound. Most likely KIH-keh-roh is how Cicero's name would have been pronounced during his time, when Classical Latin was spoken. Subsequently, in Ecclesiastical Latin, the "c" was pronounced with a "ch" sound, which is still typical in Italian, therefore pronouncing Cicero as CHIH-cheh-roh. The pronunciation of Cicero with an "s" most likely derives from Medieval French and was adopted in English speaking countries, where most people pronounce Cicero as SIH-seh-roh.
The audio pronunciation contains the pronunciation of Marcus Tullius Cicero in Classical Latin, thus pronounced as KIH-keh-roh.