Try this. Go to the MASTER CHANNEL fat channel window by pressing the MASTER select button on the lower right area of the console. Double click the "Select" button in the MASTER section of the console. Make sure that the PRE- and POST- insert are assigned to "NONE". This can also be achieved by creating a BRAND NEW session. But... I have had similar issues when routing the Final Mix plugin to the Master Bus and then removing the plug-in from the Plug In window. When you delete from the PlugIn window, it doesnt normalize the Master section to "NONE" Sometimes the MASTER PRE- and POST- will be routed to an EMPTY Plug In channel. If there is no Plug In assigned to the Plug In slot, a zero-routing will occur. You will need to set MASTER PRE- and POST- insert to "NONE". Try that. If that does not solve the issue, create a new session, and follow the SPOON FED details. Those instructions work just fine with a fresh session. Once you get your fresh setup, make THAT your startus session.
Hope that helps... some!
Tavon