My HD DVD player won't read disks

Question

We have a Toshiba SD-V55HTSU which was working just fine. We inadvertently played a 0 region Pink Floyd DVD which has apparently corrupted our internal software. Now we cannot read any DVD's except our JVC lens cleaner. Toshiba told us to take to an authorized repair shop, the shop says our only fix is to get the firmware disk from Toshiba, who then told us the disk is not available for our model. Can anybody help us - is there anything we can do to salvage this very nice Home Theater that we just inherited in October?