Read the tip of SynVox elsewhere in this forum ....
"For the subtitle problem i use a workaround with PgcEdit (a free program, which can manipulate the stream information in the *.IFO Files). I just reassign the subtitle-stream-numbers greater 0 to all 4 screen formats (4:3, 16:9, letterbox, pan&scan) with PgcEdit. By default the numbers are only set for the corresponding screen formats, so a typical 16:9 DVD has the numbers set only for formats 16:9 and letterbox, the other two always read 0. As the N35 only looks at the 4:3-format-info regardless the actual format of the movie, it always selects subtitle-stream 0 (the 1. or default subtitle language). By for example changing the info for subtitle-stream 1 from 0-1-1-0 to 1-1-1-1 with PgcEdit the N35 is then able to select the correct subtitle-stream .
The procedure is quite fast and easy to perform at least with raw DVD rips, so for me it's a very useful and painless workaround, until a fix is delivered in one of the next firmwares. "