Ok, so I recently purchased a new computer from ADK (excellent machine, stats below) and I transferred my old projects folder from the old machine to my audio drive on my new machine. These are per-project folders. Some of these projects were recorded @24/48K, and some @ 24/44.1. My new "Preferences" settings for Bit rate are 44.1 Khz. I opened an older project that was 48K bit rate and started having problems with the audio engine stopping, and had to reboot to get it going again.

I've only been using a DAW for around five years, and I'm not that knowledgeable with computers. I've learned a lot, but I'm not sure if it matters if a 48K project is opened when the preferences bit rate is set to 44.1K. I researched the help files, searched this forum, and cannot find an answer. Will someone kindly educate me?  Thank you.

With the project closed, used r8brain from voxengo to convert the wav files and then reopen the project.
All should be well.
That's what I did when I changed from 48k to 44.1k.

Thanks gustabo for the info. One thing though, for the life of me I cannot figure out how to tell the bit rate of a project before opening it. I guess I'm just getting old, seems like it should be so simple.

Load any audio file from a project into r8brain and it'll tell you what it is.

Thank you very much! 

Hope it helps.
Btw, Voxengo has two versions of r8brain, a free and a pro.
They both do the same thing but the free version will convert less number of files at a time and r8brain pro will do folders at a time, kind of like a batch file.

Thanks again, I'll give it a try.