I just received the cartridge today, and it worked for about 10 minutes, but now when I turn it on, all I get is a black screen. I tried removing the SD card and plugging into the computer with the USB cable and opening up the software (in OS X), but I get a red light and it says "Harmony Cart not found" Is there anything I can do about this or is it broken?
I know the USB cable works because I had used it to load data onto the SD card. It also fails when I try connecting with the SD card in the cartridge.
I tried two different USB cables and three different USB ports.