Issue with Forced VOBSUB in Phantom Menace

[Gorgonite]

Hello All,

First time poster so be gentle.
Ive been happily ripping away all of my DVD collection over the last few months, having taken the time to learn the process and make sure I do it right (as i want my mkvs).
For each MKV i like to keep the full english subs (usually track 1) and any seperate forced subs (usually track 3)

I have come across the a DVD with a problem i cannot figure out is Star Wars Episode 1 - The Phantom Menace.
I can pick the video and audio titles fine. I can even determine which subs i want to keep - Track 1 is the full English subs, Track 2 is the forced subs for alien dialogue i want to keep.

I can rip these absolutely fine BUT the problem comes to when I playback the forced subs - they just don't play!
The full English subs (track 1) play fine in VLC and at 31:42 Watto speaks his first words in alien language and they are displayed in english as expected for the full subtitles track.
The forced subs however display nothing throughout the entire movie even during the alien dialogue parts including 31:42.
I have tried playing it through VLC and Plex but still the second subtitle track shows nothing.
I opened the mkv in subedit and can see (just) the forced dialogue in track 2.

What am i doing wrong? Is there something wrong with vobsub track 2?

Thanks in advance

[Woodstock]

Star Wars often has a lot more subtitle tracks than normal. Sometimes there are commentary tracks. And sometimes, non-essential dialog isn't subtitled at all.

[drxenos]

This is a known issue with that DVD, you need to fix the transparency or else the subtitles are invisible. I extracted them, ran them through bdsup2sub with the --fix-invisible option, and remuxed them into the mkv file. Some DVD rippers like AnyDVD (if you can still run it) or XReveal have a setting that can purported fix the transparency but I've never tried it.