Firmware probs

Hi, i’ve got a LVW-5002, my original SN was: 0103-3244-0094-B207
I did update of firmware en now i have SN:0103-3244-0098-B208 (015-01D)

The problem is that i can’t playback most of the copy’s i’ve made(since the update). the only disks he still plays are original’s, phillips and fuji disks.

is there a way of turning back to the original SN? or to downgrade or something esle?

Maybe some other way to solve the disks problem?

Many thanks in advance.