  Spoken language recognition (SLR) is the task of automatically identifying
the language present in a speech signal. Existing SLR models are either too
computationally expensive or too large to run effectively on devices with
limited resources. For real-world deployment, a model should also gracefully
handle unseen languages outside of the target language set, yet prior work has
focused on closed-set classification where all input languages are known
a-priori. In this paper we address these two limitations: we explore efficient
model architectures for SLR based on convolutional networks, and propose a
multilabel training strategy to handle non-target languages at inference time.
Using the VoxLingua107 dataset, we show that our models obtain competitive
results while being orders of magnitude smaller and faster than current
state-of-the-art methods, and that our multilabel strategy is more robust to
unseen non-target languages compared to multiclass classification.
