diff --git a/companion/src/firmwares/rawsource.cpp b/companion/src/firmwares/rawsource.cpp
index eaa651b6c..98fa363d4 100644
--- a/companion/src/firmwares/rawsource.cpp
+++ b/companion/src/firmwares/rawsource.cpp
@@ -343,8 +343,10 @@ RawSource RawSource::convert(RadioDataConversionState & cstate)
   if (type == SOURCE_TYPE_STICK) {
     QStringList fromStickList(getStickList(cstate.fromBoard));
     QStringList toStickList(getStickList(cstate.toBoard));
-    index = toStickList.indexOf(fromStickList.at(oldData.id));
-    // index set to -1 if no match found
+    if (oldData.id < fromStickList.count())
+      index = toStickList.indexOf(fromStickList.at(oldData.id));
+    else
+      index = -1;
     // perform forced mapping
   }