diff --git a/diffsynth/models/wan_video_vae.py b/diffsynth/models/wan_video_vae.py
index 3c2181abf..3d5db6801 100644
--- a/diffsynth/models/wan_video_vae.py
+++ b/diffsynth/models/wan_video_vae.py
@@ -469,7 +469,7 @@ def __init__(
     def forward(self, x, feat_cache=None, feat_idx=[0]):
         x_copy = x.clone()
         for module in self.downsamples:
-            x = module(x, feat_cache, feat_idx)
+            x, feat_cache, feat_idx = module(x, feat_cache, feat_idx)
 
         return x + self.avg_shortcut(x_copy), feat_cache, feat_idx
 
@@ -506,10 +506,10 @@ def __init__(
     def forward(self, x, feat_cache=None, feat_idx=[0], first_chunk=False):
         x_main = x.clone()
         for module in self.upsamples:
-            x_main = module(x_main, feat_cache, feat_idx)
+            x_main, feat_cache, feat_idx = module(x_main, feat_cache, feat_idx)
         if self.avg_shortcut is not None:
             x_shortcut = self.avg_shortcut(x, first_chunk)
-            return x_main + x_shortcut
+            return x_main + x_shortcut, feat_cache, feat_idx
         else:
             return x_main, feat_cache, feat_idx