Here are some DTP-L1500 elusive firmwares, dumped straight from my own DTP-L1500 units for preservation purposes.
I would assume you could generate a PSAR or write a flasher for those if you would be so inclined. Unfortunately, as far as I know of there are no DTP-L1500 updates available outside of Sony, Anyway here they are:
2.50 Rev B AVTool:
mega.nz
3.51 Rev A AVTool:
mega.nz
Enjoy!
I would assume you could generate a PSAR or write a flasher for those if you would be so inclined. Unfortunately, as far as I know of there are no DTP-L1500 updates available outside of Sony, Anyway here they are:
2.50 Rev B AVTool:
25.49 MB file on MEGA
3.51 Rev A AVTool:
26.14 MB file on MEGA
Enjoy!