I just bought 2 of these recently and am having a bit of trouble. One of them is hanging at the loading screen. Both did this at first but after a day or so one began to work perfectly. The other has never worked. I've swapped the micro SD cards over and both work in the working cart and neither work in the other. I know it's a contact issue and have tried the paper fix to no avail. Is there anything else I can try or is it just knackered? Could it be my DS by any chance? A loose cart slot for example?