Same here. Computer voice, really loud and annoying.

Received calls on unlisted numbers from this number with a recorded "debt" message

Got a call from them on my office phone line (a I've never given away to anyone). Generic eletronic recording marketting debt solutions. If you can stand listning to the message long enough, they tell you to hit 9 to remove your number from their list. Lets see if it actually works.

Same thing...debt scam.  Calls are circulating all through our office here (people all have similar #s)

Called me on my cell. How can we stop that scum?

It's possible that this is just a stage 1 phishing attempt. They don't identify themselves, and you have the opportunity to hit 1. When you do that they then jot down in their database that you are a possible gullible target, someone to peddle products to. That in itself could actually be their actual product. The whole credit story could just be a story just to measure to see if you respond.
They're just profiling you.
Once you respond, you go into another database and you get sold off to a range of actual other marketing slime.

They sadly don't indentify which company they're calling from / on behalf of.

One of us will have to have enough courage to hit 1 :)