Not sure any (program) hack would be possible, even per-game. The ADPCM left and right channel values are interleaved, and the hardware itself reads it from memory based on start/end addresses (with 256-byte granularity) programmed into the registers. There's no data path between the VROM and the YM2610 that can be manipulated by the Z80.Had to ask anyway.
Individual hacks for each game then? How about a toggle in the NeoSD menu?
Heh. It may be obvious for many reading this. Bitmap Bureau disovered a previously undocumented bug in NEO-YSA2 last year: The ADPCM-B channels are swapped!What are you trying to achieve and why?