Index: mptrack/PatternEditorDialogs.cpp
===================================================================
--- mptrack/PatternEditorDialogs.cpp	(revision 12033)
+++ mptrack/PatternEditorDialogs.cpp	(working copy)
@@ -880,7 +880,7 @@
 	CMainFrame *pMainFrm;
 
 	CDialog::OnInitDialog();
-	m_Keyboard.Init(m_hWnd, 2);
+	m_Keyboard.Init(m_hWnd, 4);
 	pMainFrm = CMainFrame::GetMainFrame();
 	if (!pMainFrm) return TRUE;
 	// Fills the shortcut key combo box
@@ -893,20 +893,20 @@
 
 	// Minor notes
 	CString s;
-	for (int inotes=-1; inotes<24; inotes++)
+	for (int inotes = -25; inotes < 24; inotes++)
 	{
-		if(inotes < 0)
+		if(inotes == -25)
 		{
 			s = _T("--");
 		} else
 		{
 			s = mpt::ToCString(CSoundFile::GetDefaultNoteName(inotes % 12));
-			if(inotes >= 12)
-				s.AppendFormat(_T(" (+%d)"), inotes / 12);
+			if(inotes < 0 || inotes >= 12)
+				s.AppendFormat(_T(" (%c%d)"), inotes < 0 ? '-' : '+', inotes / 12);
 		}
-		m_CbnNote1.AddString(s);
-		m_CbnNote2.AddString(s);
-		m_CbnNote3.AddString(s);
+		m_CbnNote1.SetItemData(m_CbnNote1.AddString(s), inotes);
+		m_CbnNote1.SetItemData(m_CbnNote2.AddString(s), inotes);
+		m_CbnNote1.SetItemData(m_CbnNote3.AddString(s), inotes);
 	}
 	// Update Dialog
 	OnChordChanged();
@@ -932,11 +932,11 @@
 	chord.notes[0] = NOTE_NONE;
 	chord.notes[1] = NOTE_NONE;
 	chord.notes[2] = NOTE_NONE;
-	for(UINT i = 0; i < 2 * 12; i++)
+	for(UINT i = 0; i < 4 * 12; i++)
 	{
 		if(chord.key == MPTChord::relativeMode)
 		{
-			if(!i) continue;
+			if(i == 2 * 12) continue;
 		} else
 		{
 			if(i == chord.key % 12u) continue;
@@ -949,7 +949,7 @@
 			if ((cnote < 3) || (i == (UINT)nKey))
 			{
 				UINT k = (cnote < 3) ? cnote : 2;
-				chord.notes[k] = static_cast<BYTE>(i+1);
+				chord.notes[k] = static_cast<int8>(i + 1);
 				if (cnote < 3) cnote++;
 			}
 		}
Index: mptrack/TrackerSettings.cpp
===================================================================
--- mptrack/TrackerSettings.cpp	(revision 12033)
+++ mptrack/TrackerSettings.cpp	(working copy)
@@ -393,15 +393,15 @@
 		if(ichord < 12)
 		{
 			// Major Chords
-			Chords[ichord].notes[0] = (uint8)(ichord+5);
-			Chords[ichord].notes[1] = (uint8)(ichord+8);
-			Chords[ichord].notes[2] = (uint8)(ichord+11);
+			Chords[ichord].notes[0] = (int8)(ichord+5);
+			Chords[ichord].notes[1] = (int8)(ichord+8);
+			Chords[ichord].notes[2] = (int8)(ichord+11);
 		} else if(ichord < 24)
 		{
 			// Minor Chords
-			Chords[ichord].notes[0] = (uint8)(ichord-8);
-			Chords[ichord].notes[1] = (uint8)(ichord-4);
-			Chords[ichord].notes[2] = (uint8)(ichord-1);
+			Chords[ichord].notes[0] = (int8)(ichord-8);
+			Chords[ichord].notes[1] = (int8)(ichord-4);
+			Chords[ichord].notes[2] = (int8)(ichord-1);
 		}
 	}
 
@@ -1238,9 +1238,9 @@
 			if((chord & 0xFFFFFFC0) || (!chords[i].notes[0]))
 			{
 				chords[i].key = (uint8)(chord & 0x3F);
-				chords[i].notes[0] = (uint8)((chord >> 6) & 0x3F);
-				chords[i].notes[1] = (uint8)((chord >> 12) & 0x3F);
-				chords[i].notes[2] = (uint8)((chord >> 18) & 0x3F);
+				chords[i].notes[0] = static_cast<int8>(((chord >> 6) & 0x3F) | (0xC0 * ((chord >> 11) & 1)));
+				chords[i].notes[1] = static_cast<int8>(((chord >> 12) & 0x3F) | (0xC0 * ((chord >> 17) & 1)));
+				chords[i].notes[2] = static_cast<int8>(((chord >> 18) & 0x3F) | (0xC0 * ((chord >> 23) & 1)));
 			}
 		}
 	}
@@ -1251,7 +1251,7 @@
 {
 	for(std::size_t i = 0; i < std::size(chords); i++)
 	{
-		int32 s = (chords[i].key) | (chords[i].notes[0] << 6) | (chords[i].notes[1] << 12) | (chords[i].notes[2] << 18);
+		int32 s = (chords[i].key) | ((chords[i].notes[0] & 0x3F) << 6) | ((chords[i].notes[1] & 0x3F) << 12) | ((chords[i].notes[2] & 0x3F) << 18);
 		mpt::ustring note = mpt::format(U_("%1%2"))(mpt::ustring(NoteNamesSharp[i % 12]), i / 12);
 		conf.Write<int32>(U_("Chords"), note, s);
 	}
Index: mptrack/TrackerSettings.h
===================================================================
--- mptrack/TrackerSettings.h	(revision 12033)
+++ mptrack/TrackerSettings.h	(working copy)
@@ -193,7 +193,7 @@
 	};
 
 	uint8 key;			// Base note
-	uint8 notes[3];		// Additional chord notes
+	int8 notes[3];		// Additional chord notes
 };
 
 using MPTChords = std::array<MPTChord, 3 * 12>;	// 3 octaves
Index: mptrack/View_pat.cpp
===================================================================
--- mptrack/View_pat.cpp	(revision 12033)
+++ mptrack/View_pat.cpp	(working copy)
@@ -5195,7 +5195,7 @@
 	{
 		if(cnote)
 		{
-			ModCommand::NOTE chordNote = key - NOTE_MIN;
+			int32 chordNote = key - NOTE_MIN;
 			if(!relativeMode)
 			{
 				// Only use octave information from the base key
@@ -5202,9 +5202,9 @@
 				chordNote = (chordNote / 12) * 12;
 			}
 			chordNote += cnote;
-			if(specs.HasNote(chordNote))
+			if(chordNote >= NOTE_MIN && chordNote <= NOTE_MAX && specs.HasNote(static_cast<ModCommand::NOTE>(chordNote)))
 			{
-				outNotes[numNotes++] = chordNote;
+				outNotes[numNotes++] = static_cast<ModCommand::NOTE>(chordNote);
 			}
 		}
 	}