This article aims to shed light on the intricacies that overturn McLuhan's vision of technologies as extensions or prosthetics of human capabilities when applied to human-machine communication (HMC). Human and nonhuman entities co-evolve on an equal agential footing, immersed in mediatized assemblages. Building on the concepts of Deleuze and Guattari, Bennett, and others, it theorizes HMC as a cycle of sonic enchantment, culminating in trans-corporeal surrogacy, disrupted by disenchantment, and started again through re-enchantment. A new materialist framework helps explain the process of posthuman HMC. It provides a close-textual and visual analysis of Spike Jonze's film Her (2013), in which a human develops a romantic relationship with his AI assistant. The aspects of vulnerability, neediness, authenticity, trust, and intimacy surpass the lure of real-time personalized audio communication. The paper argues that artificial intelligence acquires autonomous agency through the processes of enchantment and mutual surrogacy that decenter humans in mediatized assemblages.