The TTS Samantha voice for igo speaks gibberish when paired with Samantha tts for vocalizerex and I haven't found any other US female voices for igo. The only other US female voices for vocalizer is Allison and Aba and neither is available for igo that I've found.

Am using Nexus 4, with 4.4.4 Android, and vocalizerex of vocalizer_e.tts_1.0.2.3k, and igo primo 9.6.29.383117