Hello, I'm Jewel with Kingston Technical Support and would like to offer our assistance. We do have several different types of 64GB SDXC cards, currently available are SDX10V/64GB (UHS-I), SD10G3/64GB (UHS-I Elite), and SDA10/64GB (UHS-I Ultimate) each card is faster than the next. Panasonic's product page does suggest one of their UHS-I Ulitimate cards with the same specifications as our fastest card (SDA10/64GB) for your camcorder so there should be no compatibility issues. Have you been able to format the card in your Sony camera and then see if it is recognized in your camcorder? We may need to do further research into the issue and will need more specifics off the Kingston Card you have (the one that works and the one that doesn't) which will help us decipher the issue. Please call us at 1-800-435-0640 (USA and Canada only) M - F 6am - 6pm PT and I or another available Technician will assist you. Please be sure to have the part in question on hand when you call.
Thank you for selecting Kingston as your upgrade partner.