Spyro 2 and 3 Audio Issue with PSX Emulator

FrenchAussie

I used the built in speakers for two TVs.

Oh I forgot to mention, I also tried different games of course and they all work fine (Crash, Croc, Tekken 3)

mitu

Are you using the standalone pcsx-rearmed or the Libretro based core (lr-pcsx_rearmed) ? Do you have Enhanced graphics turned on ?

FrenchAussie

It's the standard PCSX ReArmed r22 - version 1.7.5.

Turning off the enhancers also causes the same issue.

FrenchAussie

@mitu so sorry, I just realised I checked in the wrong place. It's in my retropie installs so it's the lr-pcsx-rearmed version

mitu

I gave it a try on my PI3B with Spyro 2 and I don't get any sound "popping". Used the same BIOS (scph1001), but this doesn't seem to make a difference. Is the sound problem always present or does it appear on/after certain parts of the game - I only played around the 1st level for about 20 min ? I've used a .bin/.cue (redump validated).

FrenchAussie

@mitu it happens all the time during gameplay. every time i start running around a lot and the scene is changing fast that's when its more likely to 'pop'. And yeah only with those two games. Just tried Ape's Escape and everything was fine with that game too

pjft

So, I'm trying it out, played for a few minutes after the intro and I get no meaningful popping as well. I lost audio halfway through the intro, interestingly. But skipping the intro I got audio back.

I'm on lr-pcsx-rearmed r22, it seems, under RetroArch 1.7.1?

Potentially relevant:
Quick Menu > Options:

Vibration: disabled
Sound: Reverb: enabled (default, I think)
Sound: Interpolation: off (default, I think)

Settings > Audio:

Volume (dB): 0.0
Mixer: 0.0
Audio Sync: On
Latency: 64ms
Resampler Quality: Lower
Dynamic Audio Rate Control: 0.005
Audio Max Timing Skew: 0.05
Output Rate: 44100

Settings > Driver:

Audio driver: alsathread
Audio resampler driver: sinc

Alternatively, if you have a spare SD card around, I'd start from a fresh image and see if it works well. It might be something with a recent RetroArch or emulator update?

FrenchAussie

@pjft Thank you so much! I have found the problem thanks to you! Sound: Interpolation was set on 'simple'. I'm not sure if this is the default version of 1.7.5 or whether I clicked it by accident but either way its now set to 'off'. I'm so thankful! I've been at it for 3 days!

pjft

@FrenchAussie glad to hear that worked.

A question, while we're at it -- does your sound cut off in the intro (when the "bad guy" shows up complaining that they brought a dragon over or something - I'm not familiar with the lore here :) ) in the USA rom?

Thanks.

FrenchAussie

@pjft yes it does. from what i've been reading on the forums, it seems like everyone with USA rom versions has this issue. Not sure about the EU version i only tested the gameplay with it.

pjft

@FrenchAussie Thanks - good to know. I won't worry about it then.

hhromic

@FrenchAussie said in Spyro 2 and 3 Audio Issue with PSX Emulator:

@pjft Thank you so much! I have found the problem thanks to you! Sound: Interpolation was set on 'simple'. I'm not sure if this is the default version of 1.7.5 or whether I clicked it by accident but either way its now set to 'off'. I'm so thankful! I've been at it for 3 days!

According to the libretro docs the default is set to simple for the lr-pcsx-rearmed core (is not a general RA option):

Sound: Interpolation [pcsx_rearmed_spu_interpolation] (simple|gaussian|cubic|off)
Modify sound interpolation.

I'm curious if the sound quality suffers noticeable when disabling the interpolation? Do you notice any perceptible (audible) difference?

FrenchAussie

@hhromic a little but its nothing major. when spyro jumps, there's a slightly higher pitch in sound but this is nothing compared to the 'pop' sound i was getting. spyro 2 definitely cannot have enhanced graphics as it messes up with a few things. overall, a very sensitive game to modification.

hhromic

Update

A pull-request (PR) has been submitted to the upstream pcsx_rearmed core that improves the gaussian audio interpolation algorithm. If/when this PR gets merged, maybe you can give another try to Spyro 2/3 and see if the sounds doesn't crack anymore and the sound quality improves thanks to the interpolation. Hopefully gaussian interpolation is not so taxing to the RPI.

Ref: https://github.com/libretro/pcsx_rearmed/pull/218