CHIRP

I have read and tried the solutions found here by reading through some threads. Nothing I have tried has had any success. Here's what I've got:
Programming cable from Valley Enterprises. Additional cable from no-name Chinese manufacturer. Both of these cables successfully read from my radio using G4HFQ software. So I know I am putting the radio in Clone mode correctly and that cable is not the issue. Each and every time I use Chirp, I get the following message: Failed to communicate with radio: Failed to read header
This is the port that shows up in Chirp when I connect my cable: /dev/cu.usbserial-AH02TVBM. I am wondering if I should see "/dev/tty.usbserial-AH02TVBM". I can see this in Terminal, but it does not appear when connecting the cable in Chirp
I am using OSX but have the identical problem in Windows 7. I correctly select the correct COM port, but the error message and symptoms are the same.