diff --git a/USER_MANUAL.md b/USER_MANUAL.md
index 2f13dcfd..eda10347 100644
--- a/USER_MANUAL.md
+++ b/USER_MANUAL.md
@@ -957,7 +957,7 @@ LDPC | Low Density Parity Check Codes - a family of powerful FEC codes
     * Fix potential equalizer bug that could introduce corrupted audio. (PR #1480)
     * Fix uninitialized value read during waterfall plot render. (PR #1481)
     * Match std::atomic memory ordering to what each atomic actually synchronises. (PR #1482)
-    * Remove use of mutexes in audio path during callsign decode. (PR #1486)
+    * Remove use of mutexes in audio path during callsign decode. (PR #1486, #1493)
     * Tighten audio thread timings on macOS and Windows. (PR #1494)
 2. Build system:
     * Windows versions are now built with llvm-mingw 20260908 (PR #1489)
diff --git a/src/freedv_interface.cpp b/src/freedv_interface.cpp
index a47160dd..139221fe 100644
--- a/src/freedv_interface.cpp
+++ b/src/freedv_interface.cpp
@@ -122,7 +122,7 @@ void FreeDVInterface::OnRadeTextRx_(rade_text_t, const char* txt_ptr, int, void*
     
     char tmpBuf[RELIABLE_TEXT_FIFO_SIZE];
     memset(tmpBuf, 0, RELIABLE_TEXT_FIFO_SIZE);
-    strncpy(tmpBuf, txt_ptr, RELIABLE_TEXT_FIFO_SIZE);
+    strncpy(tmpBuf, txt_ptr, RELIABLE_TEXT_FIFO_SIZE - 1);
     obj->reliableTextFifo_.write(tmpBuf, RELIABLE_TEXT_FIFO_SIZE);
 }