Is there any motion on this? There are some older software / WAPP solutions to unlock the GM/GX features of the FP-30, and I was seeing if hardware was another option. Also, the stereo line out would be huge!

Link to schematics

https://www.docdroid.net/ptgwaKy/fp-30-ksc-70-pdf

I also am into hacking the FP30. But on a different level (low level).I successfully duped the internal flash and instrument bank.
I am searching for someone able to understand how data is organized so we could make an editor and get a better piano (I hate the tuning of the main piano). You can find the dumped data here: https://github.com/Zibri/FP30

Hi, could you tell me how you dumped the internal flash of your FP30? I'd like to do the same with my FP10, and then If I succesfully decrypt the .img files I'd like to compare the two.

I already posted my dump. If you want to analyze it it's at the link above. Comparing it to FP10 or FP60 won't help because they will probably be similar but the FP10 will be shorter and FP60 probably bigger.

Roland just released the FP30x  - and with the X they have now added line out to the keyboard. This is so frustrating 

They also removed a few features. What's worse: after 2 years one of the keys (I rarely platyed) is not working.. and I hear people with 3-8 kdead keys after even less than an year.

I would try to follow the traces from the speakers or the headphones. Hopefully they should start from a chip which datasheet is available.
The path is probably something like CPU / sound engine -> DAC -> amplifier, but the DAC and amplifier can be the same component.

However, there is also a chance that audio out is handled by another PCB on the sister models that have it. Come connectors are not soldered on you board, so this must be a modular system.

In any case, if you can hear sound from the keyboard, one way or another there must be a place you can pick a line-level signal.

Thank you Pierre-Loup!

I’m searching for a wiring diagram/  service manual online.   Any tip on how to get it?