The Slingbox addon is very taxing on the computer's resources. There isn't much that we can do to help, especially because Mozilla doesn't not provide technical support for third party addons like Slingbox. For more assistance, please contact Slingbox. You can view these articles for more information on how to improve the performance of Firefox: *[[Firefox uses too much memory (RAM) - How to fix]] *[[Firefox uses too many CPU resources - How to fix]] *[[Firefox is slow - How to make it faster]] *[[Firefox hangs or is not responding - How to fix]]