Hebrew subtitles not displaying correctly on 1.6.15 ver

after the problem had been solved  on 1.5.04 ver,  on 1.6.15 ver, hebrew subtitles  not displaying correctly.

i wish WD company will resolve the problem in the next version.

for now i want to ask if i can upgrade back to 1.5.04 ver without damage the device?

thank you.

Yes, you can rollback: http://wdc.custhelp.com/app/answers/detail/a_id/5800