diff --git a/crates/ml/src/cuda_pipeline/gpu_backtest_evaluator.rs b/crates/ml/src/cuda_pipeline/gpu_backtest_evaluator.rs
index 7706b6ad2..a5b8c80f6 100644
--- a/crates/ml/src/cuda_pipeline/gpu_backtest_evaluator.rs
+++ b/crates/ml/src/cuda_pipeline/gpu_backtest_evaluator.rs
@@ -981,6 +981,7 @@ impl GpuBacktestEvaluator {
                     .arg(&1.0_f32)     // eps_urg_mult (no-op at eps=0)
                     .arg(&(chunk_start as i32)) // timestep for stateless Philox RNG
                     .arg(&0u64)                // per_sample_epsilon: NULL → use cosine schedule
+                    .arg(&0u64)                // isv_signals_ptr: NULL → static hold (backtest)
                     .launch(launch_cfg)
                     .map_err(|e| MLError::ModelError(format!(
                         "chunked action_select chunk_start={chunk_start}: {e}"
diff --git a/test_data/feature-cache/9412eb8eddebfb1935378b13c5c87e05ead68044198c67912a3a06cdc20514fb.fxcache b/test_data/feature-cache/9412eb8eddebfb1935378b13c5c87e05ead68044198c67912a3a06cdc20514fb.fxcache
new file mode 100644
index 000000000..d39630ced
Binary files /dev/null and b/test_data/feature-cache/9412eb8eddebfb1935378b13c5c87e05ead68044198c67912a3a06cdc20514fb.fxcache differ