Genesis Plus GX and Mega CD games: audio doesn't seem to sync properly

Libretro
#1

Hi everyone, I’m having this little problem with Genesis Plus GX, while running Mega CD and SEGA-CD games on RetroArch, Windows 10 1903.

I’m using redumps of games I own in my retrogame collection, so I know them pretty well and I noticed a couple of quirks right away.

I launched Annet Futatabi first, which seemed to work prefectly - the speech during cutscenes sounds synced to me - until I noticed a split-second pause right at the beginning of each stage, that doesn’t happen in the actual game. Same thing with Bari-Arm: there’s this odd pause at the start of each level, plus a slight sound delay during the Human logo (it cuts the jingle quite abruptly, instead of playing it to the end), the whole intro and also the transformation cutscene after each bossfight.

Any idea about what is causing this?

Can it be simple access to my laptop’s internal HDD? I store all my retro emulators and games there, so I don’t touch the system’s primary SSD unit for gaming purposes. Or maybe is there anything I need to tweak in RA or Genesis Plus GX before launching my games?

Thanks in advance! ^_-

#2

I haven’t tested those games, but when I was testing it a little bit ago, Lunar 1 (Redump verified) seemed synced up in the first cutscene where you meet Luna. I don’t have any specific settings changed to make sync better. Running it on a WD Blue HDD. It is converted into CHD format, but I don’t think that affects sync any.

1 Like
#3

Thanks for helping out, really appreciate that.

I’m a bit lost, honestly. My laptop should have the specs to ensure perfect emulation, and in fact the game (talking about Bari-Arm specifically, here) runs pretty perfectly. I know it very well and I can tell there’s nothing wrong anywhere, aside from the sound delay I mentioned earlier.

What’s weird, it doesn’t seem to change even if I try different combinations:

A) RetroArch on my internal, data hard-drive + Bari-Arm on the same HDD

B) same + Bari-Arm on the Windows SSD unit

C) same + Bari Arm (not the Redump version, but instead the CUE/CCD/SUB/image package) on an external USB Seagate Portable drive

No matter what, the amount of sound delay remains the same: doesn’t get better or worse, the Human jingle cuts just about a split second before the regular timing.

Edit - I also tried to convert the cue/bin folder into a CHD file, to swap different Japanese BIOS files (MCD, MCD2, etc…), and to launch the game through Picodrive. Unfortunately, nothing changed.

#4

Tested Bari-Arm (Japan) and also noticed the Human logo sound being cut off and the beginning of level pauses. Since you’ve tested those on real hardware, you could report the issues on the GPGX libretro repo. There’s already this recent report that looks pretty similar to your issues though.

1 Like
#5

Thanks for looking that up, I’ll definitely report the issue at the link you provided.

Edit - And done, reported. Thanks again for the link.

As an aside - after trying Bari-Arm with Picodrive (same results) - I also tested it with Kega Fusion, and the sound delay/cut there is way more noticeable, even with Perfect Sync option enabled.

Trying to find different/better working redumps or sets doesn’t sound to me like a possible solution, am I right?