diff --git a/Modem.cpp b/Modem.cpp
index 1e35bf3..f34ac4a 100644
--- a/Modem.cpp
+++ b/Modem.cpp
@@ -1032,7 +1032,7 @@ bool CModem::sendCWId(const std::string& callsign)
 
 	// CUtils::dump(1U, "Written", buffer, length + 3U);
 
-	return m_serial.write(buffer, length + 3U) == (length + 3U);
+	return m_serial.write(buffer, length + 3U) == int(length + 3U);
 }
 
 bool CModem::writeDMRStart(bool tx)