Blank lines causing Activity Feed problem...

I think there's problem with the activity feed. I hope you guys look into the matter.

Here's the Error message:
---------------------------------

XML Parsing Error: XML or text declaration not at start of entity
Location: http://www.xxxxxxxxx.com/xml/notifica...
Line Number 4, Column 1:<?xml version="1.0" encoding="utf-8"?>
^

I think there are some blank spaces before the xml feed starts that's causing the problem.