Can Large Audio Language Models Ignore Multilingual Distractors? An Evaluation of Their Selective Auditory Attention Capabilities

Abstract: Robust selective auditory attention under multilingual interference is critical for reliable deployment of Large Audio LLMs (LALMs). We introduce MUSA, a cocktail party-inspired multilingual benchmark for source-grounded spoken-language understanding and reasoning. Each item pairs an English target dialogue with a semantically plausible distractor in English, Spanish, Korean, or Chinese, and evaluates models across (1) single, (2) source separation-based two-stage, (3) and end-to-end cocktail party settings under controlled SNRs. Evaluating two closed-source and four open-weight LALMs, we find that strong single performance does not ensure robust selective auditory attention: cocktail party accuracy degrades under severe SNRs, and errors are dominated by distractor-grounded source confusion. In addition, separation reduces acoustic overlap but leaves source attribution unresolved, often yielding confident wrong-stream answers. Data and code will be released upon publication.