I'm brand new to Audacity...and I need help

I’m using Audacity 2.2.1. “Record” only works when I select “built-in mic.” If I select “M-box mini” mic, it will not record (by the way, I always plug-in my mic before opening Audacity). Also, when I DO record with “built-in” mic, then edit out a segment, hit rewind, then play, it just freezes. It will not play. Lastly, I get the spinning wheel, quite a bit on my iMac. What am I doing wrong? Help.

What version of Mac OS are you using, and what Mac model?

– Bill