Every time as in when you run through OOBE for the first time (supply username, computername, product key, etc.), then restart the computer it prompts for the same information?
If so that would be highly unusual, and if you are using an answer file I would suspect something in that answer file might be responsible. Make sure you validate your answer files with Windows System Image Manager (WSIM). Also be sure your anti-virus or security software is disabled if you have installed it in the native image, sometimes security can block Sysprep from accessing certain files or configurations and cause Sysprep to fail or behave weirdly like what you described.
You mentioned “joining it back to our domain”. When you create a system image, you really shouldn’t join the machine to the domain. In fact the best practice that we promote is to keep the reference environment as simple as possible. Install it in a virtual machine to prevent complex drivers from installing, install as little software as possible and configure only things that must be configured during reference image creation (like CopyProfile). For installing drivers, applications, and configuring Windows we really recommend you use a modern automated deployment tool like the Microsoft Deployment Toolkit (MDT) that will do these tasks during deployment. It makes the process easy to repeat and change time after time and minimizes compatibility issues with different hardware or app configs.
Windows Outreach Team- IT Pro
Windows for IT Pros at TechNet