Microsoft has released the following KB article:
Custom port settings are not added to boot media in System Center 2012 Configuration Manager
Summary:
Boot media that is created at a central administration site (CAS) server in a Microsoft System Center Configuration Manager 2012 or System Center Configuration Manager 2012 R2 hierarchy will not contain the custom client communication port numbers of a child site. This occurs with dynamic or site-based media. However, this occurs only when the media is created on a site that has port numbers that are different from the port numbers of the site on which the client will be deployed.
Errors that resemble the following will be recorded in the Smsts.log file on the destination computer. Notice that the port reference will continue to read “:80” instead of the custom port that was previously defined for the site.
Error. Status code 404 returned
Boot media contains custom port information only for the site at which the media was created. For a site that has different port settings, client computers will not connect to the management point for that site. Media that is created at a stand-alone site is not affected and contains custom port information.
Full details at:
http://support.microsoft.com/kb/2952919