Panasonic DMR-E55 doesn't read RAM or -R?

My DMR-E55 will not read or record to any new DVD-RAM (Panasonic brand) or DVD-R disks (TDK brand). It will record/play to original DVD-RAM disks bought 2 years ago with the unit, but with newer disks, I get "Can Not Read" and "Needs Formatting" messages. When I try to format under the Functions menu, it states that the disk is not compatible, is not a re-writable disk, etc. I've tried disks from different batches. I tried Firmware upgrade but got "Unsupport" message meaning upgrade is already in unit. Panasonic technical support says to take to repair center, but I figure that I will only end up paying more than a new one would cost. Please, does anyone have any ideas or suggestions? Thanks.