Update modeling_acestep_v15_base.py

fix issue: https://github.com/ace-step/ACE-Step-1.5/issues/214

modeling_acestep_v15_base.py

@@ -1939,7 +1939,8 @@ class AceStepConditionGenerationModel(AceStepPreTrainedModel):
                 # Update x_t based on inference method
                 if infer_method == "sde":
                     # Stochastic Differential Equation: predict clean, then re-add noise
-                    pred_clean = self.get_x0_from_noise(xt, vt, t_curr_tensor)
+                    t_curr_bsz = t_curr * torch.ones((bsz,), device=device, dtype=dtype)
+                    pred_clean = self.get_x0_from_noise(xt, vt, t_curr_bsz)
                     next_timestep = 1.0 - (float(step_idx + 1) / infer_steps)
                     xt = self.renoise(pred_clean, next_timestep)
                 elif infer_method == "ode":