How to remove the first line from RSS feeds?

[Danny_HR]

As the title says, i would like to remove the first line, well actually first two lines from my rss feed.

I have set up my RSS to drag only topics for my one forum, cause i use it as a news forum.
Now, in each topic i put in the news forum, the first line is an image, and second is blank.
I would like to remove the image from the RSS feed.

I know i need to edit my external.php file in order to do so, i just dont know what to do.

So, my question, what should i do with the external.php file to remove those lines when my from my RSS?

Any help will be greatly appreciated.