diff --git a/companion/src/datamodels/rawsourceitemmodel.cpp b/companion/src/datamodels/rawsourceitemmodel.cpp
index cc54b3bec..afb39ec05 100644
--- a/companion/src/datamodels/rawsourceitemmodel.cpp
+++ b/companion/src/datamodels/rawsourceitemmodel.cpp
@@ -50,7 +50,7 @@ RawSourceItemModel::RawSourceItemModel(const GeneralSettings * const generalSett
   addItems(SOURCE_TYPE_GVAR,           RawSource::GVarsGroup,    fw->getCapability(Gvars));
 }
 
-void RawSourceItemModel::setDynamicItemData(QStandardItem * item, const RawSource & src)
+void RawSourceItemModel::setDynamicItemData(QStandardItem * item, const RawSource & src) const
 {
   Board::Type board = getCurrentBoard();
   item->setText(src.toString(modelData, generalSettings, board));
@@ -70,7 +70,7 @@ void RawSourceItemModel::addItems(const RawSourceType & type, const unsigned gro
   }
 }
 
-void RawSourceItemModel::update()
+void RawSourceItemModel::update() const
 {
   for (int i=0; i < rowCount(); ++i)
     setDynamicItemData(item(i), RawSource(item(i)->data(ItemIdRole).toInt()));
@@ -107,18 +107,19 @@ void RawSourceFilterItemModel::setFilterGroups(unsigned groups)
 
 bool RawSourceFilterItemModel::filterAcceptsRow(int sourceRow, const QModelIndex & sourceParent) const
 {
-  bool ok = true;
   const QModelIndex & srcIdx = sourceModel()->index(sourceRow, 0, sourceParent);
-  if (!sourceModel()->data(srcIdx, filterRole()).toBool())
+  if (!srcIdx.isValid() || !sourceModel()->data(srcIdx, filterRole()).toBool())
     return false;
+
   if (filterGroups && filterGroups != RawSource::AllSourceGroups) {
+    bool ok;
     const unsigned group = sourceModel()->data(srcIdx, RawSourceItemModel::ItemGroupRole).toUInt(&ok);
     return (ok && (filterGroups & group));
   }
   return true;
 }
 
-void RawSourceFilterItemModel::update()
+void RawSourceFilterItemModel::update() const
 {
   RawSourceItemModel * model = qobject_cast<RawSourceItemModel *>(sourceModel());
   if (model)
diff --git a/companion/src/datamodels/rawsourceitemmodel.h b/companion/src/datamodels/rawsourceitemmodel.h
index 0f5b827b8..ac4337d31 100644
--- a/companion/src/datamodels/rawsourceitemmodel.h
+++ b/companion/src/datamodels/rawsourceitemmodel.h
@@ -39,10 +39,10 @@ class RawSourceItemModel: public QStandardItemModel
     RawSourceItemModel(const GeneralSettings * const generalSettings, const ModelData * const modelData, QObject * parent = nullptr);
 
   public slots:
-    void update();
+    void update() const;
 
   protected:
-    void setDynamicItemData(QStandardItem * item, const RawSource & src);
+    void setDynamicItemData(QStandardItem * item, const RawSource & src) const;
     void addItems(const RawSourceType & type, const unsigned group, const int count, const int start = 0);
 
     const GeneralSettings * generalSettings;
@@ -66,7 +66,7 @@ class RawSourceFilterItemModel: public QSortFilterProxyModel
 
   public slots:
     void setFilterGroups(unsigned groups);
-    void update();
+    void update() const;
 
   protected:
     bool filterAcceptsRow(int sourceRow, const QModelIndex & sourceParent) const override;
diff --git a/companion/src/modeledit/telemetry.cpp b/companion/src/modeledit/telemetry.cpp
index 3a0cdc0d9..39cd025b9 100644
--- a/companion/src/modeledit/telemetry.cpp
+++ b/companion/src/modeledit/telemetry.cpp
@@ -320,8 +320,7 @@ TelemetryAnalog::~TelemetryAnalog()
 TelemetryCustomScreen::TelemetryCustomScreen(QWidget *parent, ModelData & model, FrSkyScreenData & screen, GeneralSettings & generalSettings, Firmware * firmware, RawSourceFilterItemModel * srcModel):
   ModelPanel(parent, model, generalSettings, firmware),
   ui(new Ui::TelemetryCustomScreen),
-  screen(screen),
-  rawSourceItemModel(srcModel)
+  screen(screen)
 {
   ui->setupUi(this);
 
@@ -329,7 +328,7 @@ TelemetryCustomScreen::TelemetryCustomScreen(QWidget *parent, ModelData & model,
     for (int c=0; c<firmware->getCapability(TelemetryCustomScreensFieldsPerLine); c++) {
       fieldsCB[l][c] = new QComboBox(this);
       fieldsCB[l][c]->setProperty("index", c + (l<<8));
-      fieldsCB[l][c]->setModel(rawSourceItemModel);
+      fieldsCB[l][c]->setModel(srcModel);
       ui->screenNumsLayout->addWidget(fieldsCB[l][c], l, c, 1, 1);
       connect(fieldsCB[l][c], SIGNAL(activated(int)), this, SLOT(customFieldChanged(int)));
     }
@@ -338,7 +337,7 @@ TelemetryCustomScreen::TelemetryCustomScreen(QWidget *parent, ModelData & model,
   for (int l=0; l<4; l++) {
     barsCB[l] = new QComboBox(this);
     barsCB[l]->setProperty("index", l);
-    barsCB[l]->setModel(rawSourceItemModel);
+    barsCB[l]->setModel(srcModel);
     connect(barsCB[l], SIGNAL(activated(int)), this, SLOT(barSourceChanged(int)));
     ui->screenBarsLayout->addWidget(barsCB[l], l, 0, 1, 1);
 
diff --git a/companion/src/modeledit/telemetry.h b/companion/src/modeledit/telemetry.h
index a69b27e27..b23214927 100644
--- a/companion/src/modeledit/telemetry.h
+++ b/companion/src/modeledit/telemetry.h
@@ -90,7 +90,6 @@ class TelemetryCustomScreen: public ModelPanel
     void updateBar(int line);
     Ui::TelemetryCustomScreen * ui;
     FrSkyScreenData & screen;
-    RawSourceFilterItemModel * rawSourceItemModel;
     QComboBox * fieldsCB[4][3];
     QComboBox * barsCB[4];
     QDoubleSpinBox * minSB[4];