There is an issue affecting Auto-Tune® 8 that causes the Auto-Tune Update Checker pop-up window to frequently appear when loading the plugin. The only way to permanently resolve the issue is to disable automatic update checking in the Options dialog window.
To do this, click on the Options button in the upper right corner of the Auto-Tune 8 window and then uncheck the "Automatically check for updates" box. Then make sure the "Save as Default" box is checked, and click on "Save" to save the setting as a default preference.
Make sure your Options screen matches the screenshot below and click "Save" to permanently disable update checking and resolve the issue.