Audio CDs not being recognized

[network23]

I recently picked up two audio CDs that were recorded using some semi-pro equipment. When I put either one in my MBP, both appear in the Finder as unformatted, ready-to-record CDs. At first, I thought the church's duplicator was acting up, or someone accidentally labeled some blank CDs, but then I tried playing them in my car CD player and they played just fine.

I think this has happened to me before, where a recorded audio CD wasn't recognized.

Any ideas why this is happening and how to fix it?

Thanks!