Jacek Rozenek, who has voiced Geralt in Polish since the first Witcher game, is returning for The Witcher 3: Songs of the Past, though his new lines are being run through an AI voice model so they match his original Witcher 3 performance. CD Projekt Red told Game File it worked with Ukrainian AI firm Respeecher on this, with Rozenek's approval. The actor suffered a stroke in 2019 that left him unable to speak for months, and his voice is now lower and gruffer than in the roughly 10,000 lines he recorded for the base game in 2014. CDPR feared the mismatch would stand out, since new battle cries and one-liners can play in older parts of the map too.

Rozenek still performs every line himself. Respeecher's model, trained on his original Witcher 3 recordings, then reshapes the new takes to match how Geralt sounded in 2015. Rozenek himself weighed in on this, saying the point is that this voice should be as close as possible to his voice from 12 years ago. Localization producer Mikołaj Szwed called it a "special case" tied to Rozenek's health and said CDPR's contracts require consent for any AI work. He sees this as a way to use AI "ethically, with consent and also to do something good." Doug Cockle's English Geralt, apparently, needed no such treatment.CDPR has used Respeecher once before, in Cyberpunk 2077: Phantom Liberty, where another actor recorded new lines for Viktor Vektor and the software made them sound like the late Miłogost Reczek, with his family's blessing. We get to hear Rozenek in The Witcher 3: Songs of the Past, due in 2027 as a paid expansion.