Yes, the Vx2 is limited to 2GB SD cards. It could be the machine has a bad card reader and it needs service or it doesn't like the formatting used or the media brand. Normally when you open the new SD card pack you shouldn't do anything to it. The SD card formatting is what is needed. If having no choice to format it should be done in a PC not a MAC and in FAT File format. If you think it is the media, your Furuno dealer can order the Furuno USA 2GB chips (pn SD1-BNK-003) if needed.