diff --git a/DMRTX.cpp b/DMRTX.cpp
index a9a4690..e34ea60 100644
--- a/DMRTX.cpp
+++ b/DMRTX.cpp
@@ -378,7 +378,9 @@ void CDMRTX::createCACH(uint8_t txSlotIndex, uint8_t rxSlotIndex)
     m_cachPtr = 0U;
 
   if (m_cachPtr == 0U) {
-    if (m_fifo[0U].getData() == 0U && m_fifo[1U].getData() == 0U)
+    if ((m_fifo[0U].getData() == 0U && m_fifo[1U].getData() == 0U) && !m_trunking)
+      ::memcpy(m_shortLC, EMPTY_SHORT_LC, 12U);
+    else
       ::memcpy(m_shortLC, m_newShortLC, 12U);
   }