diff --git a/CalibTracker/SiPixelLorentzAngle/src/SiPixelLorentzAnglePCLHarvester.cc b/CalibTracker/SiPixelLorentzAngle/src/SiPixelLorentzAnglePCLHarvester.cc
index d267b82338538..3ebde9fa1bf33 100644
--- a/CalibTracker/SiPixelLorentzAngle/src/SiPixelLorentzAnglePCLHarvester.cc
+++ b/CalibTracker/SiPixelLorentzAngle/src/SiPixelLorentzAnglePCLHarvester.cc
@@ -102,10 +102,10 @@ class SiPixelLorentzAnglePCLHarvester : public DQMEDHarvester {
   const std::string recordName_;
   std::unique_ptr<TF1> f1;
   float width_;
+  float theMagField_{0.f};
 
   SiPixelLorentzAngleCalibrationHistograms hists;
   const SiPixelLorentzAngle* currentLorentzAngle;
-  const MagneticField* magField;
   std::unique_ptr<TrackerTopology> theTrackerTopology;
 };
 
@@ -133,9 +133,13 @@ void SiPixelLorentzAnglePCLHarvester::beginRun(const edm::Run& iRun, const edm::
   const TrackerGeometry* geom = &iSetup.getData(geomEsToken_);
   const TrackerTopology* tTopo = &iSetup.getData(topoEsTokenBR_);
 
-  magField = &iSetup.getData(magneticFieldToken_);
+  const MagneticField* magField = &iSetup.getData(magneticFieldToken_);
   currentLorentzAngle = &iSetup.getData(siPixelLAEsToken_);
 
+  // B-field value
+  // nominalValue returns the magnetic field value in kgauss (1T = 10 kgauss)
+  theMagField_ = magField->nominalValue() / 10.;
+
   PixelTopologyMap map = PixelTopologyMap(geom, tTopo);
   hists.nlay = geom->numberOfLayers(PixelSubdetector::PixelBarrel);
   hists.nModules_.resize(hists.nlay);
@@ -580,10 +584,6 @@ SiPixelLAHarvest::fitResults SiPixelLorentzAnglePCLHarvester::fitAndStore(
   // output results
   SiPixelLAHarvest::fitResults res;
 
-  // B-field value
-  // nominalValue returns the magnetic field value in kgauss (1T = 10 kgauss)
-  float theMagField = magField->nominalValue() / 10.;
-
   double half_width = width_ * 10000 / 2;  // pixel half thickness in units of micro meter
 
   f1 = std::make_unique<TF1>("f1", "[0] + [1]*x + [2]*x*x + [3]*x*x*x + [4]*x*x*x*x + [5]*x*x*x*x*x", 5., 280.);
@@ -640,8 +640,8 @@ SiPixelLAHarvest::fitResults SiPixelLorentzAnglePCLHarvester::fitAndStore(
        pow((half_width * half_width * half_width * half_width * res.e5), 2));  // Propagation of uncertainty
   res.error_LA = sqrt(errsq_LA);
 
-  hists.h_bySectMeasLA_->setBinContent(i_index, (res.tan_LA / theMagField));
-  hists.h_bySectMeasLA_->setBinError(i_index, (res.error_LA / theMagField));
+  hists.h_bySectMeasLA_->setBinContent(i_index, (res.tan_LA / theMagField_));
+  hists.h_bySectMeasLA_->setBinError(i_index, (res.error_LA / theMagField_));
   hists.h_bySectChi2_->setBinContent(i_index, res.redChi2);
   hists.h_bySectChi2_->setBinError(i_index, 0.);  // no errors
 
@@ -672,7 +672,7 @@ SiPixelLAHarvest::fitResults SiPixelLorentzAnglePCLHarvester::fitAndStore(
   float currentLA = currentLorentzAngle->getLorentzAngle(detIdsToFill.front());
   // if the fit quality is OK
   if ((res.redChi2 != 0.) && (res.redChi2 < fitChi2Cut_) && (nentries > minHitsCut_)) {
-    LorentzAnglePerTesla_ = res.tan_LA / theMagField;
+    LorentzAnglePerTesla_ = res.tan_LA / theMagField_;
     // fill the LA actually written to payload
     hists.h_bySectSetLA_->setBinContent(i_index, LorentzAnglePerTesla_);
     hists.h_bySectRejectLA_->setBinContent(i_index, 0.);
@@ -690,7 +690,7 @@ SiPixelLAHarvest::fitResults SiPixelLorentzAnglePCLHarvester::fitAndStore(
   } else {
     // just copy the values from the existing payload
     hists.h_bySectSetLA_->setBinContent(i_index, 0.);
-    hists.h_bySectRejectLA_->setBinContent(i_index, (res.tan_LA / theMagField));
+    hists.h_bySectRejectLA_->setBinContent(i_index, (res.tan_LA / theMagField_));
     hists.h_bySectLA_->setBinContent(i_index, currentLA);
     hists.h_bySectDeltaLA_->setBinContent(i_index, 0.);
 
diff --git a/MagneticField/GeomBuilder/plugins/dd4hep/DD4hep_VolumeBasedMagneticFieldESProducerFromDB.cc b/MagneticField/GeomBuilder/plugins/dd4hep/DD4hep_VolumeBasedMagneticFieldESProducerFromDB.cc
index 4a9e5d0e6bdfa..e21f52421ad54 100644
--- a/MagneticField/GeomBuilder/plugins/dd4hep/DD4hep_VolumeBasedMagneticFieldESProducerFromDB.cc
+++ b/MagneticField/GeomBuilder/plugins/dd4hep/DD4hep_VolumeBasedMagneticFieldESProducerFromDB.cc
@@ -50,6 +50,7 @@ namespace magneticfield {
   class DD4hep_VolumeBasedMagneticFieldESProducerFromDB : public edm::ESProducer {
   public:
     DD4hep_VolumeBasedMagneticFieldESProducerFromDB(const edm::ParameterSet& iConfig);
+    ~DD4hep_VolumeBasedMagneticFieldESProducerFromDB() override;
     // forbid copy ctor and assignment op.
     DD4hep_VolumeBasedMagneticFieldESProducerFromDB(const DD4hep_VolumeBasedMagneticFieldESProducerFromDB&) = delete;
     const DD4hep_VolumeBasedMagneticFieldESProducerFromDB& operator=(
@@ -73,6 +74,8 @@ namespace magneticfield {
     edm::ESGetToken<MagFieldConfig, IdealMagneticFieldRecord> chosenConfigToken_;
 
     edm::ESGetToken<FileBlob, MFGeometryFileRcd> mayConsumeBlobToken_;
+    cms::DDDetector* detector_{nullptr};
+
     const bool debug_;
     const bool useMergeFileIfAvailable_;
   };
@@ -130,6 +133,10 @@ DD4hep_VolumeBasedMagneticFieldESProducerFromDB::DD4hep_VolumeBasedMagneticField
   chosenConfigToken_ = cc.consumes(myConfigTag);  //Use same tag as the choice
 }
 
+DD4hep_VolumeBasedMagneticFieldESProducerFromDB::~DD4hep_VolumeBasedMagneticFieldESProducerFromDB() {
+  delete detector_;
+}
+
 std::shared_ptr<MagFieldConfig const> DD4hep_VolumeBasedMagneticFieldESProducerFromDB::chooseConfigAtRuntime(
     IdealMagneticFieldRecord const& iRcd) {
   edm::ESHandle<MagFieldConfig> config = iRcd.getHandle(mayGetConfigToken_);
@@ -187,9 +194,10 @@ std::unique_ptr<MagneticField> DD4hep_VolumeBasedMagneticFieldESProducerFromDB::
       "<MaterialSection label=\"materials.xml\"><ElementaryMaterial name=\"materials:Vacuum\" density=\"1e-13*mg/cm3\" "
       "symbol=\" \" atomicWeight=\"1*g/mole\" atomicNumber=\"1\"/></MaterialSection>");
 
-  auto ddet = make_unique<cms::DDDetector>("cmsMagneticField:MAGF", sblob, true);
+  if (nullptr == detector_)
+    detector_ = new cms::DDDetector("cmsMagneticField:MAGF", sblob, true);
 
-  builder.build(ddet.get());
+  builder.build(detector_);
 
   // Build the VB map. Ownership of the parametrization is transferred to it
   return std::make_unique<VolumeBasedMagneticField>(conf->geometryVersion,