diff --git a/.riahub/workflows/train.yaml b/.riahub/workflows/train.yaml
index e1982d1..ce5bada 100644
--- a/.riahub/workflows/train.yaml
+++ b/.riahub/workflows/train.yaml
@@ -15,7 +15,7 @@ permissions:
 
 jobs:
   WavesFM-Training:
-    runs-on: "ubuntu-24.04"
+    runs-on: "ubuntu-latest-2080"
     env:
       WAVESFM_TASK: "rml"
       WAVESFM_EPOCHS: "10"
@@ -27,6 +27,9 @@ jobs:
       # downstream step uses the env var, no hard-coded paths.
       WAVESFM_REPO_DIR: "/opt/wavesfm/repo"
       WAVESFM_ADAPTED_DATA: "/opt/wavesfm/adapted_data.h5"
+      # Override model-download base URL to internal LAN IP
+      # (external riahub.ai LFS endpoint is unreachable from runners).
+      RIAHUB_BASE_URL: "http://192.168.0.170:3000"
     steps:
       - name: Display basic runner info
         run: |
@@ -294,7 +297,7 @@ jobs:
           # `--device cpu` from the Train step actually takes effect.
           # No-op if the line already uses args.device (idempotent).
           if [[ -f main_finetune.py ]]; then
-            sed -i 's|torch\.amp\.GradScaler(device="cuda")|torch.amp.GradScaler(device=args.device, enabled=(args.device != "cpu"))|' main_finetune.py
+            sed -i 's|torch\.amp\.GradScaler(device="cuda")|torch.cuda.amp.GradScaler(enabled=(args.device != "cpu"))|' main_finetune.py
             echo "Patched main_finetune.py GradScaler for CPU/GPU device parity."
           fi
 
@@ -331,6 +334,10 @@ jobs:
           # only when the repo is genuinely installable (has setup.py /
           # setup.cfg, or pyproject.toml with [build-system]).
           cd "$WAVESFM_REPO_DIR"
+          # Pre-install CPU torch + numpy<2 to make requirements.txt see them already-satisfied (saves ~600MB).
+          # torch 2.2.2 has the NumPy 1.x ABI and crashes if numpy 2.x is installed.
+          $PIP install --index-url https://download.pytorch.org/whl/cpu --extra-index-url https://pypi.org/simple "numpy<2" "torch==2.2.2" torchvision
+          $PIP install --upgrade --force-reinstall "numpy<2"
           INSTALLED_SOMETHING=0
           if [[ -f requirements.txt ]]; then
             $PIP install -r requirements.txt
@@ -347,6 +354,8 @@ jobs:
             exit 1
           fi
           $PIP install h5py scipy
+          # Force numpy<2 again (requirements.txt may have bumped it via transitive deps).
+          $PIP install --upgrade --force-reinstall "numpy<2"
           TORCH_INDEX_URL="https://download.pytorch.org/whl/cpu"
           TORCH_REASON="no NVIDIA GPU detected"
           if command -v nvidia-smi &> /dev/null; then
@@ -366,7 +375,8 @@ jobs:
             fi
           fi
           echo "Installing PyTorch from ${TORCH_INDEX_URL} (${TORCH_REASON})."
-          $PIP install --index-url "$TORCH_INDEX_URL" --upgrade --force-reinstall torch torchvision
+          # torch pre-installed at step head; force-reinstall disabled to avoid 755MB redownload
+          echo "Skipping torch force-reinstall ($TORCH_INDEX_URL)"
 
       - name: Find and adapt dataset
         shell: bash
@@ -462,4 +472,4 @@ jobs:
             ${{ env.WAVESFM_OUTPUT_DIR }}/best.pth
             ${{ env.WAVESFM_OUTPUT_DIR }}/log.txt
           if-no-files-found: warn
-# committed at 2026-05-28T10:47:45.318818+00:00
+# committed at 2026-05-28T11:01:57.936314+00:00