Nothing is downloading
I just bought the doggcatcher app yesterday for my Droid Incredible, and subscribed to a bunch of podcasts. I downloaded a handful of new episodes, but after about 6 or 7 downloaded successfully, they just started failing. The cause says unknown. I tried again today, and still nothing. I've tried re-loading the podcast feed. Still nothing. Whats going on?
Can you post the error detail? That has the true error message, the cause is just a guess for some common types of problems.
DC stores all the media on the external sd card by default.
You can configure the location to be your internal storage by changing the storage location preference (I think it's way down at the bottom of the preferences.
The location is going to vary by device, but I think for the incredible it's /emmc
You'll also need to move your media from the external storage card to your internal storage.

java.io.IOException: No Space left on device
I just noticed that the memory on my SC card is full, but there is plenty of space on the internal phone memory storage.