I cannot get my flv files to load in Firefox but they work perfect in IE… My system is running apache.
Finally, I found out that the problem was related with the Hotlink Protection implemented by some hosts through the .htaccess file and the fact that Flash does not send the referrer and Firefox does not add it to the request.
After some research I found this workaround adding some lines in the .htaccess file:
RewriteEngine on
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http(s)?://(www\.)?yoursite.com [NC] RewriteRule \.(jpg|jpeg|png|gif|flv)$ – [NC,F,L]
This solved my problem.