got a call from 866-577-9590.
answered, said hello, went to a dial tone

Called them back and got abby from JP Christianson. Wouldn't tell me what they did or why they would call me, so I hung up.

It is a collection Agency based out of Los Angeles.  They are a scam.

No, It's a huge Corporation based out of Sauk Rapid Minnesota, here the detailed contact enformation:

   JC Christensen And Associates, Inc.  (866)577-9590
   215 Benton Drive                     (866)552-3365
   Sauk Rapids, Minnesota  56379-9590  
  These are some of the upper Coporate Board:
   Chuck Engebretson's
   Matt Schmit
   Jim Christensen
   Jean Miller
   Mark Kottke    Scum Bag is to nice of a word for this trash,so if they can
 harass you by all means this is a free country harass the hell out of this
 corporate board! give them some of there own medicine

They called me from 866-245-5344 from JP Christianson.  I have told them repeatedly and so has my boyfriend that these are new numbers and they continue to call thinking we are the people who use to have these phones.   I think they need a class action suit for harrassment....

So, you people really think we're scammers and frauds? Do you realize we are a whole industry of licensed, regulated people who are watched very closely so as NOT to break the laws of the FDCPA?  If we have a number on our dialer, it is because we were given that number by the companies that hire us to collect bad debt.  Guess who supplies the companies with the number?  You got it!  Consumers!  Do the right thing. Take responsibility for your actions and pay your bills.  I know the economy sucks but we are all living in it, you debtors are not special cases.  Get a job, get a loan, get a friend, do whatever you have to do to fulfill your legal obligation.  You signed on the line and that is a binding contract.  We are reasonable and willing to work with you but swearing at us and refusing to pick up the phone does no one any favors.

Sorry, but I've been called repeatedly by agencies despite not having debt of any kind looking for people with similar names in the same area. I used to cooperate with them, but my number still comes up despite having demonstrated that I was not the person they  were seeking.
There are also numerous boiler rooms that call to arrange debt consolidation scams.
Perhaps you're working for a more well-run and legitimate firm than either of those, but your rhetoric sounds parroted from management's spiel to make you feel better about harassing people, some or many of whom many not have had any relationship with the firms that provide business to your firm.
Firms that offer credit or loans to bad prospects are going to have to learn to stop doing so, just as consumers who take on more debt than they can handle are going to have to learn to stop doing so.
I know the economy's rough, but please try to get a decent, productive job as soon as possible.