How can I get my Panasonic DMR-ES46V to recognize DVDs again?

My Panasonic DRM-ES46V just began not recognizing any DVD disc---pre-recorded or otherwise (get the "no read" error). Panasonic "tech support" had me do the chan up/down and power reset with no change. (Their solution is to send it to their exchange center for a cost about the same as I paid for it new)Is this problem repairable and if so how??? Thanks!