After using apogee duet, mac's built in mic & logic's track headers for recording are not working properly. How do I fix it?

Question

I use logic 9
After using apogee duet for mac, I was away from my home studio without the duet and wanted to record vocals via the internal microphone on my mac book pro.  (Obviously, I know it wouldn’t be the same quality.  I wanted to do it as a draft, because I had a melody in my head and wanted to record it so I could remember it later.)
After opening up a project I was unable to record audio.  I noticed the track headers had changed.  Sometimes the “record ready” button was missing.  But whether it was there or wasn’t, the same thing kept happening… After pressing the “record button” or the “record ready” button a window would pop up that said, “No input source selected!”  I tried to trouble shoot by configuring track header and by going to prefereces>audio>devices>core audio, and switched the “input device” to “built in microphone,” and things like that, but I still would get the same pop up window indicating “no input source selected.”   To be thorough, in preferences under “core audio,” I have selected universal track mode, 24 bit recording, and software monitoring.
Do I need to reset something?
If your recommendations help fix the immediate issue temporarily, how do I keep it from reverting back to the same problem if I feel like switching between the duet interface and the built in mic in the future?  How do I keep it permanently from this malfunction?  It seems like this is something simple that would be addressed.
Also, as I was trying to think of anything it could possibly be.  I wonder if it could be the driver I installed for an old m-box2 possibly causing an issue.  After getting my new mac book pro, I downloaded a driver for m-box2 (the second generation that came out in 2005 and used pro tools LE.)  I used the m-box on my previous computer and it worked well.  Since I purchased a new macbook, I tried to use it on my new computer, but since the m-box2 is a 32 bit system, it didn’t work very well, which is why I got the duet.  I don’t know if that could possibly be messing anything up.  If so, should I uninstall it somehow?
Thanks

Answer 1

Ok, think this through... you've changed from a stereo source to a mono source.
The message reads: “No input source selected!”
On the track you're trying to record there is an Input section directly underneath the  I/O label. Click and hold to select the correct Input for that track.
Also, the project you opened was saved with the Duet's driver/interface parameters.. if you open the same project without the audio interface Logic will do it's best to pick I/O that's compatible but I've never seen any DAW do this perfectly.. it always takes a small amount of user input. Especially since you've changed from the Apogee to the internal mic.