diff --git a/codes/trainer/injectors/audio_injectors.py b/codes/trainer/injectors/audio_injectors.py
index ffb1b43a..1f799113 100644
--- a/codes/trainer/injectors/audio_injectors.py
+++ b/codes/trainer/injectors/audio_injectors.py
@@ -74,11 +74,15 @@ class RandomAudioCropInjector(Injector):
     def __init__(self, opt, env):
         super().__init__(opt, env)
         self.crop_sz = opt['crop_size']
+        self.lengths_key = opt['lengths_key']
 
     def forward(self, state):
         inp = state[self.input]
-        len = inp.shape[-1]
+        lens = state[self.lengths_key]
+        len = torch.min(lens)
         margin = len - self.crop_sz
+        if margin < 0:
+            return {self.output: inp}
         start = random.randint(0, margin)
         return {self.output: inp[:, :, start:start+self.crop_sz]}