Try to directly link the banner,
example:

src"http://mysite.com/themes/mytheme/banner.swf"

Use the flash codebase when you code it into the html.

If you need the flash codebase I can post it for you.
Also a question, is your domain name cloaked or masked? This I have noticed sometime creates a slight problem. Also once you update your theme or banner page, whatever you may be doing ... be sure to delete the system generated html so that it may create a new updated version with your changes.

System html's are in the templates_c folder

I hope this helps :)

Greetings from T-Tech,

I just wanted to stop in and make a post and invite you all to stop by our community. We have devoted the biggest part of our community to the XOOPS project. Why? Well that's simple, my team has been developing modules, and working with many different CMS' that is until we came across xoops. I have to say first and forward that XOOPS in my opinion is in a class all its own. Quality, security, accessibility, simplicity and best of all some really devoted developers!
The teams has been working hard to come up with some really great mods for the XOOPS community. So far they have developed an on-site world TV module, a french tutorial module, and currently in development are a project management system, a site shouts module with admin features to change themes to match your site ect. Graphics team are working to design some flash themes for XOOPS as well, amongst other numerous projects.

Now I have to say we are not an "official" XOOPS support site, just a team of developers with a great love for the XOOPS project :)

Feel free to stop by and say hello :)
http://t-tech.org

Thanks, Danni :)