.xla ThisWorkbook module generates code on save

I have a custom add-in that I'm currently working on and recently I noticed that whenever I close down excel the add in will throw a compilation error out of the ThisWorkbook module from some code that I never put in and can't seem to delete. This is the code:

Private Sub Workbook_BeforeClose(Cancel As Boolean)
With Application.CommandBars("Panels Manager")
On Error Resume Next
.Controls("

End Sub

Every time I delete this out and close excel then re-open this code gets regenerated. I hope to deploy this add-in to other users once it's complete and I can't have it throwing an error at everyone whenever they try to use excel with the add-in loaded.

Any help is greatly appreciated,

Thanks

The add-in was created by starting from a new workbook and it has a ThisWorkbook module under the project in the VBE project toolbar. Here's a picture:

vba_projecttoolbar_pmproject.JPG

When I make the changes in VBE I save from within the editor then close down all of excel and the code is still there.

I don't think it's corruption in a .xls file, because it seems to happen regardless of what workbook I have open. I don't think I'm saving from a template, but I'll check. There may be corruption in the add-in .xla file. I'll try to unload the add-in, create a new one and copy the old code into the new add-in and see if that does it (there's not a lot in the current add-in, anyway).

Thanks for the quick response and for your suggestions!