When How You Speak Changes What Models Refuse: Investigating Prosody-Conditioned Safety Divergence in Audio-Language Models

Akash Das, Ishan Roy


Abstract
Audio-Language Models (ALMs) natively fuse lexical content with continuous paralinguistic acoustics such as intonation, tone, and speaker identity. While considerable progress has been made in aligning the semantic outputs of text-based models against harmful instructions, current ALM safety alignment evaluation largely treats speech as a noisy text channel, leaving modality-specific vulnerabilities unexamined. In this work, we introduce and investigate Prosody-Conditioned Safety Divergence: a vulnerability where an ALM’s safety behavior shifts systematically based entirely on paralinguistic variation, even when lexical semantic payload is held completely constant. Rather than assuming the existence of coarse, high-variance acoustic "authority" subspaces, we conduct a controlled causal analysis to track how specific prosodic manipulations—including variations in pitch contour and intensity—interact with safety-associated latent directions across the encoder, projector, and decoder layers. Our preliminary empirical evaluations characterize the localization of this divergence, establishing a framework for targeted inference-time interventions that restore alignment metrics without compromising baseline utility on benign speech tasks.
Anthology ID:
2026.salma-1.3
Volume:
The Proceedings of Speech and Audio Language Models Workshop (2nd Edition)
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Santosh T.Y.S.S., Sreyan Ghosh, Ramani Duraiswami, Shinji Watanabe, Siddhant Arora, Sonal Kumar, Yossi Adi, Dinesh Manocha, Leibny Paola Garcia Perera
Venues:
SALMA | WS
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
18–37
Language:
URL:
https://aclanthology.org/2026.salma-1.3/
DOI:
Bibkey:
Cite (ACL):
Akash Das and Ishan Roy. 2026. When How You Speak Changes What Models Refuse: Investigating Prosody-Conditioned Safety Divergence in Audio-Language Models. In The Proceedings of Speech and Audio Language Models Workshop (2nd Edition), pages 18–37, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
When How You Speak Changes What Models Refuse: Investigating Prosody-Conditioned Safety Divergence in Audio-Language Models (Das & Roy, SALMA 2026)
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PDF:
https://aclanthology.org/2026.salma-1.3.pdf