I remember Soundflower from my first iMac and OS 9. I am pretty sure, never positive with computer stuff, but I think Soundflower is for recording from within your computer, like if you wanted to record audio from a YouTube video in Safari. Audio Hijack Pro will do the same. You don't need Soundflower, once again, nearly positive, to record from an external source into your Mac. As I suggested before, you need to change the input device in the Sound panel in System Preferences. You can do that now with your current Mac. You can't have two audio inputs running together. In my case, the default audio input was the built-in microphone. I needed to change that to the USB turntable on my Mac, or it would not function. I left the USB turntable plugged in all the time. If I removed it, chances are I'd loose that option in the Sound panel in System Preferences. What you select in the Sound panel as your audio input device affects your Mac globally.
Well, that doesn't solve your issue. This must be some cool radio station. I use to listen to CBS Radio back when AOL partnered with them. I use the AOL Radio Player for the Mac and it worked well. I had access to many CBS radio stations, including some HD2 options, 2 or 3 from AZ even.
I think your best bet is to go with the future, a USB adapter. You could purchase the MBP 15, I won't stop you. <grin> The current iMacs don't have an audio input, but the mini does. You could consider a bare-bones <cough> Windows machine, but chances are you must get a desktop to have audio input available. Very few notebooks have audio input. If you get the MBP 15, that will keep you out of trouble until the next time, and chances are, you will be right back where you are now.
If you aren't in a hurry to get a new Mac, I'd wait for WWDC, where it seems likely Apple will at least talk about the 2013 Macs and OSX 10.9. Intel is part of the mix as well. Their 4th generation CPUs should begin to be released this month ... maybe. Stay with AI, and others for that. WWDC starts on the 10th, and that should give you some insight to the 2013 Macs.
To be clear, I had to return to Windows, as I am low vision. Typing on this website, for example is still hard, but painfully difficult with the even smaller font ratios with my 20 inch iMac. I presently have the largest screen I could find with the lowest resolution. My HP is less than 3 years old, and I've used the Recovery software many time. Not having DVDs, or something, for a Mac, would not work for me. I am constantly exploring and getting into trouble. Lastly, I don't want a totally inaccessible computer. If a hard drive fails, my pockets are not deep enough to pay a company like Apple to fix it.
I still choose to monitor Apple activity. In my mind is the option of an external drive as the boot drive. My only choices are a big screen with low resolution. Option one is a mini with a low resolution HDTV via HDMI. Option two, is a 27 inch iMac, and the ability to drop the resolution in half. Zoom makes what is already constantly blurry, even worse.
Sure, I didn't need to justify all that to you, but there are reasons I am not giving my advice on a Mac. I am an analog audio buff. Digital and I are not friends.