Sample TTS voice was probably a text-to-speech voice designed to demonstrate the difference between fully-recorded words (how he was made) and phonetics-mixing (how Microsoft Sam and all other TTS voices were made). So because of this, whatever word is not in his dictionary he'll pronounce as "blah" (example: "Hello, my name is Sample TTS voice!" will be pronounced as "Blah blah blah blah Sample TTS voice.").
Introduction to the TTS world
Sample TTS voice was brought to the text-to-speech (TTS) world by AceOfSpadesProduc100 after he got an idea when he downloaded Microsoft Speech SDK 5.1 to get Natural Microsoft Mike, and Mary (his older netbook computer came preinstalled with Natural Microsoft Sam). It somehow came with Sample TTS voice when he came to look at the natural TTS voices in the Speech Properties.
In his universe, he is a glitch TTS voice who came when Bill Gates tried to make the most natural TTS voice of all time, but his creation didn't turn out as it should be, as it almost says nothing but the word "Blah". Gates abandoned him. Sample TTS Voice discovered another glitch named Missingno. They shared their stories and followed around before and after being discovered and rescued by Microsoft Sam and the gang.
Planned series without a title yet
Missingno and Sample TTS Voice shut down the forcefield and corrupted a variant of ROFL-9000. Master Chief rescued Sample TTS Voice whilst Sam rescued Missingno.