Problems With Editing the Menu HTML

The theme I am currently using puts an unsightly >> after any menu with submenu items. I have been playing around with it and found the code that causes it using firebug. I’m just unsure of how to go about fixing it and whether to use my ftp client and notepad to make said changes.

<a href="http://www.hhshaywire.com/category/news/">
News
<span class="sub-indicator">»</span>
</a>

and this is under

<div class="header-content">
<nav id="main-nav">

I’m not sure of what I’m doing, but I do have a child theme and other basic skills down. Any help is more than greatly appreciated.

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