diff --git a/stimuli/audio/sound.py b/stimuli/audio/sound.py
index bf58288a..19ab019e 100644
--- a/stimuli/audio/sound.py
+++ b/stimuli/audio/sound.py
@@ -116,6 +116,7 @@ def _check_signal(
         the _set_signal method.
         """
         assert signal.ndim in (1, 2)
+        signal = signal.astype(np.float64)
         if signal.ndim == 2:
             assert signal.shape[1] in (1, 2)
             if signal.shape[1] == 1: