diff --git a/Decode.cpp b/Decode.cpp
index e68605a7..cb41e407 100644
--- a/Decode.cpp
+++ b/Decode.cpp
@@ -251,7 +251,7 @@ int main(int argc, char** argv) {
       FLAGS_criterion == kCtcCriterion ? tokenDict.getIndex(kBlankToken) : -1;
   int silIdx = -1;
   if (FLAGS_wordseparator != "") {
-    tokenDict.getIndex(FLAGS_wordseparator);
+    silIdx = tokenDict.getIndex(FLAGS_wordseparator);
   }
   std::shared_ptr<Trie> trie = nullptr;
   if (FLAGS_decodertype == "wrd" || FLAGS_uselexicon) {
diff --git a/src/libraries/decoder/LexiconDecoder.cpp b/src/libraries/decoder/LexiconDecoder.cpp
index 66c4cbf9..00806724 100644
--- a/src/libraries/decoder/LexiconDecoder.cpp
+++ b/src/libraries/decoder/LexiconDecoder.cpp
@@ -154,8 +154,9 @@ void LexiconDecoder::decodeStep(const float* emissions, int T, int N) {
       }
 
       /* (2) Try same lexicon node */
-      if (opt_.criterionType != CriterionType::CTC || !prevHyp.prevBlank) {
-        int n = prevIdx;
+      if (opt_.criterionType != CriterionType::CTC || !prevHyp.prevBlank ||
+          prevLex == lexicon_->getRoot()) {
+        int n = prevLex == lexicon_->getRoot() ? sil_ : prevIdx;
         double amScore = emissions[t * N + n];
         if (nDecodedFrames_ + t > 0 &&
             opt_.criterionType == CriterionType::ASG) {