diff --git a/Sources/Entities/Elemental.es b/Sources/Entities/Elemental.es
index c5b4194..16efed6 100644
--- a/Sources/Entities/Elemental.es
+++ b/Sources/Entities/Elemental.es
@@ -1324,7 +1324,7 @@ procedures:
       autocall FallOnFloor() EReturn;
     }
 
-    if (m_EecChar==ELC_LARGE || (m_EecChar==ELC_BIG && m_EetType==ELT_LAVA))
+    if ((m_EecChar==ELC_LARGE || m_EecChar==ELC_BIG) && m_EetType==ELT_LAVA)
     {
       PlaySound(m_soBackground, SOUND_LAVA_LAVABURN, SOF_3D|SOF_LOOP);
     }
diff --git a/Sources/EntitiesMP/Elemental.es b/Sources/EntitiesMP/Elemental.es
index 1c65808..2d155d8 100644
--- a/Sources/EntitiesMP/Elemental.es
+++ b/Sources/EntitiesMP/Elemental.es
@@ -1373,7 +1373,7 @@ procedures:
       autocall FallOnFloor() EReturn;
     }
 
-    if (m_EecChar==ELC_LARGE || (m_EecChar==ELC_BIG && m_EetType==ELT_LAVA))
+    if ((m_EecChar==ELC_LARGE || m_EecChar==ELC_BIG) && m_EetType==ELT_LAVA)
     {
       PlaySound(m_soBackground, SOUND_LAVA_LAVABURN, SOF_3D|SOF_LOOP);
     }
diff --git a/Sources/GameMP/Computer.cpp b/Sources/GameMP/Computer.cpp
index 60bf3cc..8a899d7 100644
--- a/Sources/GameMP/Computer.cpp
+++ b/Sources/GameMP/Computer.cpp
@@ -177,7 +177,7 @@ static PIXaabbox2D GetMsgSliderSpace(void)
 
 static PIXaabbox2D GetTextSliderBox(void)
 {
-  if (_iActiveMessage>=_acmMessages.Count()) {
+  if ((_iActiveMessage >= _acmMessages.Count()) || (_iActiveMessage < 0)) {
     return PIXaabbox2D();
   }
   INDEX ctTextLines = _acmMessages[_iActiveMessage].cm_ctFormattedLines;
@@ -246,7 +246,7 @@ void LastUnreadMessage(void)
 // go to next/previous message
 void PrevMessage(void)
 {
-  if (_iActiveMessage >= _acmMessages.Count()) {
+  if ((_iActiveMessage >= _acmMessages.Count()) || (_iActiveMessage < 0)) {
     return;
   }
   _iActiveMessage--;
@@ -258,7 +258,7 @@ void PrevMessage(void)
 
 void NextMessage(void)
 {
-  if (_iActiveMessage >= _acmMessages.Count()) {
+  if ((_iActiveMessage >= _acmMessages.Count()) || (_iActiveMessage < 0)) {
     return;
   }
   _iActiveMessage++;
@@ -305,7 +305,7 @@ void MessageTextUp(INDEX ctLines)
 void MessageTextDn(INDEX ctLines)
 {
   // if no message do nothing
-  if (_iActiveMessage >= _acmMessages.Count()) {
+  if ((_iActiveMessage >= _acmMessages.Count()) || (_iActiveMessage < 0)) {
     return;
   }
   // find text lines count
@@ -336,7 +336,7 @@ void MessageTextUpDn(INDEX ctLines)
 // mark current message as read
 void MarkCurrentRead(void)
 {
-  if (_iActiveMessage>=_acmMessages.Count()) {
+  if ((_iActiveMessage >= _acmMessages.Count()) || (_iActiveMessage < 0)) {
     return;
   }
   // if running in background