Why new card?
I have this same issue constantly. Previously it was apparently due to Google Earth. I uninstalled that, and it went away. But now it's back.
So of your two steps. 1, I cleared my cache. Nothing. You say 2 is to replace your card. Why? Are you saying that the card is most likely going bad? Because it certainly is not full, as it also wasn't in your example.
Just looking for clarification. If that's the answer, so be it. THANKS!!!!!