Your listing template may need updating.
If you are using customized templates, you may have inadvertently remove the coding necessary to display YouTube videos. If this is the case, you will need to update your product listing to include the YouTube embedding functionality on it. The code should be placed after your listing page’s main image code block. (look for the comment tag: <!–END: image1–>)
Below is the coding your listing template will need:
<iframe id=”realmedia” src=”[realmedia]” frameborder=”0″ allowfullscreen></iframe>
<li id=”showRealMedia”><i class=”icon-play”></i> <span>Video</span></li>
An easier alternative, would be to copy the listing pages from the common folder and apply them to your theme. However, this option will overwrite any possible customizations you may have applied. We recommend making a backup of your templates first before using either of these suggestions.