diff --git a/.github/workflows/build-wheels-macos-arm64.yaml b/.github/workflows/build-wheels-macos-arm64.yaml
index fe1d3162..77501043 100644
--- a/.github/workflows/build-wheels-macos-arm64.yaml
+++ b/.github/workflows/build-wheels-macos-arm64.yaml
@@ -90,7 +90,7 @@ jobs:
         run: |
           opts='--break-system-packages'
           v=${{ matrix.python-version }}
-          if [[ $v == cp37 || $v == cp38 || $v == cp39 ]]; then
+          if [[ $v == cp38 || $v == cp39 ]]; then
             opts=''
           fi
 
diff --git a/sherpa-onnx/csrc/homophone-replacer.cc b/sherpa-onnx/csrc/homophone-replacer.cc
index dc938032..69696a94 100644
--- a/sherpa-onnx/csrc/homophone-replacer.cc
+++ b/sherpa-onnx/csrc/homophone-replacer.cc
@@ -143,6 +143,12 @@ class HomophoneReplacer::Impl {
   }
 
   std::string Apply(const std::string &text) const {
+    std::string ans;
+
+    if (text.empty()) {
+      return ans;
+    }
+
     bool is_hmm = true;
 
     std::vector<std::string> words;
@@ -170,13 +176,16 @@ class HomophoneReplacer::Impl {
       pronunciations.push_back(std::move(p));
     }
 
-    std::string ans;
     for (const auto &r : replacer_list_) {
       ans = r->Normalize(words, pronunciations);
       // TODO(fangjun): We support only 1 rule fst at present.
       break;
     }
 
+    if (config_.debug) {
+      SHERPA_ONNX_LOGE("Output text: '%s'", ans.c_str());
+    }
+
     return ans;
   }