Blank line at top of file from variable text XMLPort

Hi.

I 'inherited' and XMLPort that required changes and one thing that's bugging me is there is always a blank line at the top of the output file. The output is a tab-delimited text file, and I'm thinking the node structure is the cause:

Node Name                    Node Type                Source Type         Data Source
MY_Export                      Element                    Text                    <MY_Export>
  customer                      Element                    Table                  <Customer>(Customer)
     PsalesInvLine             Element                    Table                  <Sales Invoice Line>(...
        InvNumber              Element                   Text                    <InvNumber>
        etc ...

(Sorry 'bout the formatting above ...)

The customer' node is there for filtering on the request page, and code in OnPreXMLPort cycles through the resulting customers compiling a temp table of sales invoice lines to export. A bit odd, but that's how it was built.

Anyway, the blank line at the top - I've mucked about trying all sorts of things but I either manage to get no output at all, or output with that blank line at the top.

Any comments as to why it's happening? If it's that customer node maybe I'll have to restructure the whole thing.

Thanks!