Just updated from the beta version. CC lost my name so I entered it, got the "Load new sounds" dialog, clicked "Cancel" and bang!
I can't repeat the problem so maybe it's just a one-off?

Code:
See the end of this message for details on invoking 
just-in-time (JIT) debugging instead of this dialog box.

************** Exception Text **************
System.ArgumentOutOfRangeException: InvalidArgument=Value of '-1' is not valid for 'index'.
Parameter name: index
   at System.Windows.Forms.ListBox.SetSelected(Int32 index, Boolean value)
   at CrewChiefV4.MacroEditor..ctor() in C:\projects\crewchief_c_sharp\CrewChiefV4\CrewChiefV4\UserInterface\MacroEditor.cs:line 99
   at CrewChiefV4.MainWindow.editCommandMacroButtonClicked(Object sender, EventArgs e) in C:\projects\crewchief_c_sharp\CrewChiefV4\CrewChiefV4\UserInterface\MainWindow.cs:line 3027
   at System.Windows.Forms.Control.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
   at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ButtonBase.WndProc(Message& m)
   at System.Windows.Forms.Button.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)


************** Loaded Assemblies **************
mscorlib
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3815.0 built by: NET48REL1LAST_C
    CodeBase: file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/mscorlib.dll
----------------------------------------
CrewChiefV4
    Assembly Version: 4.9.8.20
    Win32 Version: 1.0.0.0
    CodeBase: file:///C:/Program%20Files%20(x86)/Britton%20IT%20Ltd/CrewChiefV4/CrewChiefV4.exe
----------------------------------------
System.Windows.Forms
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3815.0 built by: NET48REL1LAST_C
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Windows.Forms/v4.0_4.0.0.0__b77a5c561934e089/System.Windows.Forms.dll
----------------------------------------
System
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3801.0 built by: NET48REL1LAST_B
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System/v4.0_4.0.0.0__b77a5c561934e089/System.dll
----------------------------------------
System.Drawing
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3752.0 built by: NET48REL1
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Drawing/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll
----------------------------------------
SharpDX.DirectInput
    Assembly Version: 4.2.0.0
    Win32 Version: 4.2.0
    CodeBase: file:///C:/Program%20Files%20(x86)/Britton%20IT%20Ltd/CrewChiefV4/SharpDX.DirectInput.DLL
----------------------------------------
System.Core
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3815.0 built by: NET48REL1LAST_C
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Core/v4.0_4.0.0.0__b77a5c561934e089/System.Core.dll
----------------------------------------
SharpDX
    Assembly Version: 4.2.0.0
    Win32 Version: 4.2.0
    CodeBase: file:///C:/Program%20Files%20(x86)/Britton%20IT%20Ltd/CrewChiefV4/SharpDX.DLL
----------------------------------------
System.Configuration
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3752.0 built by: NET48REL1
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Configuration/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll
----------------------------------------
System.Xml
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3752.0 built by: NET48REL1
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Xml/v4.0_4.0.0.0__b77a5c561934e089/System.Xml.dll
----------------------------------------
Newtonsoft.Json
    Assembly Version: 9.0.0.0
    Win32 Version: 9.0.1.19813
    CodeBase: file:///C:/Program%20Files%20(x86)/Britton%20IT%20Ltd/CrewChiefV4/Newtonsoft.Json.DLL
----------------------------------------
System.Numerics
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3752.0 built by: NET48REL1
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Numerics/v4.0_4.0.0.0__b77a5c561934e089/System.Numerics.dll
----------------------------------------
System.Runtime.Serialization
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3825.0 built by: NET48REL1LAST_B
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Runtime.Serialization/v4.0_4.0.0.0__b77a5c561934e089/System.Runtime.Serialization.dll
----------------------------------------
System.Xml.Linq
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3752.0 built by: NET48REL1
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Xml.Linq/v4.0_4.0.0.0__b77a5c561934e089/System.Xml.Linq.dll
----------------------------------------
System.Data
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3752.0 built by: NET48REL1
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_64/System.Data/v4.0_4.0.0.0__b77a5c561934e089/System.Data.dll
----------------------------------------
NAudio
    Assembly Version: 1.8.3.0
    Win32 Version: 1.8.3.0
    CodeBase: file:///C:/Program%20Files%20(x86)/Britton%20IT%20Ltd/CrewChiefV4/NAudio.DLL
----------------------------------------
Microsoft.Speech
    Assembly Version: 11.0.0.0
    Win32 Version: 11.0.7400.345
    CodeBase: file:///C:/WINDOWS/assembly/GAC_MSIL/Microsoft.Speech/11.0.0.0__31bf3856ad364e35/Microsoft.Speech.dll
----------------------------------------
PresentationCore
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3815.0 built by: NET48REL1LAST_C
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_64/PresentationCore/v4.0_4.0.0.0__31bf3856ad364e35/PresentationCore.dll
----------------------------------------
WindowsBase
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3815.0 built by: NET48REL1LAST_C
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/WindowsBase/v4.0_4.0.0.0__31bf3856ad364e35/WindowsBase.dll
----------------------------------------
System.Speech
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3752.0 built by: NET48REL1
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Speech/v4.0_4.0.0.0__31bf3856ad364e35/System.Speech.dll
----------------------------------------
Accessibility
    Assembly Version: 4.0.0.0
    Win32 Version: 4.8.3752.0 built by: NET48REL1
    CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/Accessibility/v4.0_4.0.0.0__b03f5f7f11d50a3a/Accessibility.dll
----------------------------------------
AutoUpdater.NET
    Assembly Version: 1.3.2.0
    Win32 Version: 1.3.2.0
    CodeBase: file:///C:/Program%20Files%20(x86)/Britton%20IT%20Ltd/CrewChiefV4/AutoUpdater.NET.DLL
----------------------------------------

************** JIT Debugging **************
To enable just-in-time (JIT) debugging, the .config file for this
application or computer (machine.config) must have the
jitDebugging value set in the system.windows.forms section.
The application must also be compiled with debugging
enabled.

For example:

<configuration>
    <system.windows.forms jitDebugging="true" />
</configuration>

When JIT debugging is enabled, any unhandled exception
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