ok I will check into things and see what I can do.  I've never had this problem before.  Sonar has always run fine on my system with all plugins.   But since I started using the CA-2A for the first time when I bought it earlier this week, that's when I've started to have the problems.
 

I think the issue was the interface driver.  I didn't realize that though my US600 tascam unit is discontinued, there was one iteration of drivers newer than I had.    Seems to work a lot better now.   funny things, those computers :)