Please refer to the attached gif file and sample project. The keyboard navigation is enabled for the items in RadCheckedListBox. However, if you press "N" (without pressing ALT) it doesn't select an item starting with "N" but selects the text box since the RadLabel's mnemonic key is "N".

Workaround:
Public Class MyLabel
    Inherits RadLabel
    Protected Overrides Function ProcessMnemonic(charCode As Char) As Boolean
        If Not (Control.ModifierKeys & Keys.Alt) <> Keys.Alt Then
            Return False
        End If

        Return MyBase.ProcessMnemonic(charCode)
    End Function
End Class