diff --git a/tests/conftest.py b/tests/conftest.py
index 66eea68538..b87822cc8d 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -684,11 +684,13 @@ def mirror_voltages():
 
 
 @pytest.fixture
-def undulator_dcm(sim_run_engine):
+def undulator_dcm(sim_run_engine, dcm, undulator):
     undulator_dcm = i03.undulator_dcm.build(
         connect_immediately=True,
         mock=True,
         daq_configuration_path="tests/test_data/test_daq_configuration",
+        dcm=dcm,
+        undulator=undulator,
     )
     set_up_dcm(undulator_dcm.dcm_ref(), sim_run_engine)
     yield undulator_dcm
diff --git a/tests/system_tests/hyperion/external_interaction/test_ispyb_dev_connection.py b/tests/system_tests/hyperion/external_interaction/test_ispyb_dev_connection.py
index ef33902031..af7afa81b0 100644
--- a/tests/system_tests/hyperion/external_interaction/test_ispyb_dev_connection.py
+++ b/tests/system_tests/hyperion/external_interaction/test_ispyb_dev_connection.py
@@ -480,8 +480,8 @@ def test_ispyb_deposition_in_gridscan(
         "orientation": "horizontal",
         "snaked": True,
         "dataCollectionId": ispyb_ids.data_collection_ids[0],
-        "micronsPerPixelX": 0.8060031111720091,
-        "micronsPerPixelY": 0.8060031111720091,
+        "micronsPerPixelX": 0.806,
+        "micronsPerPixelY": 0.806,
     }
 
     compare_actual_and_expected(