train.py: changing dataloder params given sampler

train.py

@@ -56,10 +56,14 @@ def prepare_dataloaders(hparams):
     valset = TextMelLoader(hparams.validation_files, hparams)
     collate_fn = TextMelCollate(hparams.n_frames_per_step)
 
-    train_sampler = DistributedSampler(trainset) \
-        if hparams.distributed_run else None
+    if hparams.distributed_run:
+        train_sampler = DistributedSampler(trainset)
+        shuffle = False
+    else:
+        train_sampler = None
+        shuffle = True
 
-    train_loader = DataLoader(trainset, num_workers=1, shuffle=True,
+    train_loader = DataLoader(trainset, num_workers=1, shuffle=shuffle,
                               sampler=train_sampler,
                               batch_size=hparams.batch_size, pin_memory=False,
                               drop_last=True, collate_fn=collate_fn)