Mind the Accent Gap: British Accent Robustness in Speech-Driven Financial Voice Assistants
This study addresses the limitation that existing automatic speech recognition (ASR) models are predominantly biased toward American English, which compromises the robustness of financial voice assistants to regional British accents and consequently degrades downstream tool-calling accuracy. To investigate this issue, we introduce CavaBench, the first internally collected benchmark of British-accented financial voice queries, and design an end-to-end evaluation pipeline integrating ASR with large language model reasoning to systematically assess performance from speech recognition through task execution. Our findings reveal that while word error rate (WER) serves as a strong predictor of tool-calling accuracy, it fails to adequately capture task-level performance. This work provides critical empirical evidence for designing inclusive and reliable voice interaction systems in the financial domain.