diff --git a/vocoder/datasets/gan_dataset.py b/vocoder/datasets/gan_dataset.py
index 55513e7d..af23fbf2 100644
--- a/vocoder/datasets/gan_dataset.py
+++ b/vocoder/datasets/gan_dataset.py
@@ -87,6 +87,11 @@ class GANDataset(Dataset):
                 audio, mel = self.cache[idx]
             else:
                 audio = self.ap.load_wav(wavpath)
+
+                if len(audio) < self.seq_len + self.pad_short:
+                    audio = np.pad(audio, (0, self.seq_len + self.pad_short - len(audio)), \
+                            mode='constant', constant_values=0.0)
+
                 mel = self.ap.melspectrogram(audio)
         else:
 
@@ -99,10 +104,6 @@ class GANDataset(Dataset):
                 audio = self.ap.load_wav(wavpath)
                 mel = np.load(feat_path)
 
-        if len(audio) < self.seq_len + self.pad_short:
-            audio = np.pad(audio, (0, self.seq_len + self.pad_short - len(audio)), \
-                    mode='constant', constant_values=0.0)
-
         # correct the audio length wrt padding applied in stft
         audio = np.pad(audio, (0, self.hop_len), mode="edge")
         audio = audio[:mel.shape[-1] * self.hop_len]