diff --git a/.gitea/workflows/testing.yaml b/.gitea/workflows/testing.yaml
index b6bdd09..6ed8f1a 100644
--- a/.gitea/workflows/testing.yaml
+++ b/.gitea/workflows/testing.yaml
@@ -5,7 +5,7 @@ jobs:
     runs-on: arch-x86_64
     steps:
       - name: Fetch the repository
-        run: git clone --branch ${{ gitea.ref_name }} --depth 1 ${{ gitea.server_url }}/${{ gitea.repository }}
+        run: git clone --revision ${{ gitea.sha }} --depth 1 ${{ gitea.server_url }}/${{ gitea.repository }}
 
       - name: Build containers
         run: docker-compose -f docker-compose-test.yaml build
diff --git a/agent/src/file_datasource.py b/agent/src/file_datasource.py
index 8aa8187..363f1df 100644
--- a/agent/src/file_datasource.py
+++ b/agent/src/file_datasource.py
@@ -74,8 +74,10 @@ class FileDatasource:
         self._acc_reader = csv.reader(self._acc_f, skipinitialspace=True)
         self._gps_reader = csv.reader(self._gps_f, skipinitialspace=True)
 
-        self._rewind_acc()
-        self._rewind_gps()
+        # File pointer is already at 0 right after open(), so no need to rewind here.
+        # Skip header row once.
+        next(self._acc_reader, None)
+        next(self._gps_reader, None)
 
     def _close_files(self) -> None:
         for f in (self._acc_f, self._gps_f):