The file containing these is Sp2Snd.brsar from Wii Sports Resort.
I wasn't able to submit an issue using the reporter, so I'll include the log here (this is when I tried the RBNK, but the same seems to happen for the RWSD):
Unable to cast object of type 'BrawlLib.SSBB.ResourceNodes.RBNKDataRangeTableNode' to type 'BrawlLib.SSBB.ResourceNodes.RBNKDataEntryNode'.
at BrawlLib.SSBB.ResourceNodes.RBNKTableNode.OnCalculateSize(Boolean force)
at BrawlLib.SSBB.ResourceNodes.ResourceNode.CalculateSize(Boolean force)
at BrawlLib.SSBB.ResourceNodes.RBNKDataGroupNode.OnCalculateSize(Boolean force)
at BrawlLib.SSBB.ResourceNodes.ResourceNode.CalculateSize(Boolean force)
at BrawlLib.SSBB.ResourceNodes.RBNKNode.OnCalculateSize(Boolean force)
at BrawlLib.SSBB.ResourceNodes.ResourceNode.CalculateSize(Boolean force)
at BrawlLib.Wii.Audio.RSARConverter.CalculateSize(RSAREntryList entries, RSARNode node)
at BrawlLib.SSBB.ResourceNodes.RSARNode.OnCalculateSize(Boolean force)
at BrawlLib.SSBB.ResourceNodes.ResourceNode.Rebuild(Boolean force)
at BrawlLib.SSBB.ResourceNodes.ResourceNode.Merge(Boolean forceBuild)
at BrawlCrate.Program.Save(Boolean showMessages)
at BrawlCrate.UI.MainForm.saveToolStripMenuItem_Click(Object sender, EventArgs e)
at System.Windows.Forms.ToolStripItem.RaiseEvent(Object key, EventArgs e)
at System.Windows.Forms.ToolStripMenuItem.OnClick(EventArgs e)
at System.Windows.Forms.ToolStripItem.HandleClick(EventArgs e)
at System.Windows.Forms.ToolStripItem.FireEventInteractive(EventArgs e, ToolStripItemEventType met)
at System.Windows.Forms.ToolStripItem.FireEvent(EventArgs e, ToolStripItemEventType met)
at System.Windows.Forms.ToolStripMenuItem.ProcessCmdKey(Message& m, Keys keyData)
at System.Windows.Forms.ToolStripManager.ProcessShortcut(Message& m, Keys shortcut)
at System.Windows.Forms.ToolStripManager.ProcessCmdKey(Message& m, Keys keyData)
at System.Windows.Forms.ContainerControl.ProcessCmdKey(Message& msg, Keys keyData)
at System.Windows.Forms.Form.ProcessCmdKey(Message& msg, Keys keyData)
at System.Windows.Forms.Control.ProcessCmdKey(Message& msg, Keys keyData)
at System.Windows.Forms.ContainerControl.ProcessCmdKey(Message& msg, Keys keyData)
at System.Windows.Forms.Control.ProcessCmdKey(Message& msg, Keys keyData)
at System.Windows.Forms.Control.ProcessCmdKey(Message& msg, Keys keyData)
at System.Windows.Forms.ContainerControl.ProcessCmdKey(Message& msg, Keys keyData)
at System.Windows.Forms.Control.ProcessCmdKey(Message& msg, Keys keyData)
at System.Windows.Forms.Control.ProcessCmdKey(Message& msg, Keys keyData)
at System.Windows.Forms.ContainerControl.ProcessCmdKey(Message& msg, Keys keyData)
at System.Windows.Forms.Control.ProcessCmdKey(Message& msg, Keys keyData)
at System.Windows.Forms.Control.PreProcessMessage(Message& msg)
at System.Windows.Forms.Control.PreProcessControlMessageInternal(Control target, Message& msg)
at System.Windows.Forms.Application.ThreadContext.PreTranslateMessage(MSG& msg)