Hey geetarplaya,
Oh, no, let's not just give up!
There are a few things (at least) to try.
1. Do you have a headset (earbuds with a mic in the cable)? If so, you should be able to plug it in instead of the Griffin cable and run your voice through the live effects. That would verify that the hardware jack and the app are working. (What kind of device are you using?)
2. If the Griffin cable is working properly, then you should be able to use it with other apps that record and play audio. For example, the standard Voice Memos app. Does that work?
3. One more thought is related to the headset jack on the device. Believe it or not, we have see some that don't work because they have a plug of lint in them. And it can be very difficult to get out. We've had success with compressed air, FWIW. If you have a lint plug in there, then even a headset using the Voice Memos won't work correctly.
On a related note, we have heard some reports of some Griffin cables having plugs that do not connect completely inside the jack, like they are slightly the wrong size or something. Don't know if that might apply here or not.
I hope this helps. Let us know what you learn!