diff --git a/src/h3_blackwell_runtime/packing.py b/src/h3_blackwell_runtime/packing.py
index e34f9b1..a92fe20 100644
--- a/src/h3_blackwell_runtime/packing.py
+++ b/src/h3_blackwell_runtime/packing.py
@@ -72,8 +72,8 @@ class H3PromptPacker:
             text_rows = text[0].to(torch.bfloat16)
         else:
             raise ValueError("H3 text states must be Qwen 5120-wide or refined 5376-wide.")
-        video_rows = functional.linear(patchify_video(video).float(), self.video_weight, self.video_bias).to(torch.bfloat16)
-        audio_rows = functional.linear(pack_audio(audio).float(), self.audio_weight, self.audio_bias).to(torch.bfloat16)
+        video_rows = functional.linear(patchify_video(video.to(torch.bfloat16)).float(), self.video_weight, self.video_bias).to(torch.bfloat16)
+        audio_rows = functional.linear(pack_audio(audio.to(torch.bfloat16)).float(), self.audio_weight, self.audio_bias).to(torch.bfloat16)
         text_length, audio_length = text_rows.shape[0], audio_rows.shape[0]
         hidden = torch.cat((text_rows, audio_rows, video_rows))
         video_sigma = torch.tensor(float(sigma), device=hidden.device).clamp(min=1e-6)