Many games scratchy audio

[Former user]

Original [issue 59](https://code.google.com/p/genplus-gx/issues/detail?id=59) created by westonlast on 2010-01-03T20:48:58.000Z:

Sonic the Hedgehog 2 (SEGA logo, etc.) Ecco the Dolphin (beginning, etc.) Castlevania Bloodlines (throughout)

Those are a few examples. Not sure if this was causing by the recent audio changes. Will test an older version.

[Former user]

Comment # 1 originally posted by westonlast on 2010-01-03T21:25:49.000Z:

Different revisions of Phantasy Star II are blatantly scratchy at times. It's hard to reproduce.

Vectorman was scratchy at least once.

[Former user]

Comment # 2 originally posted by westonlast on 2010-01-03T22:12:36.000Z:

This issue appeared with the recent sound revisions.

[Former user]

Comment # 3 originally posted by ekeeke31 on 2010-01-03T22:34:52.000Z:

the recent changes should not affect this, but yes scratchy sound happen sometime when loading a new game, resetting or reloading the game should fix it, this happens in earlier revision as well.

that's why it's hard to reproduce, because it's not related to a specific game and it's not constantly happening.

you can try to disable High-Quality FM and see if it still happens.

[Former user]

Comment # 4 originally posted by ekeeke31 on 2010-01-03T22:37:18.000Z:

issue \#57 has been merged into this issue.

[Former user]

Comment # 5 originally posted by ekeeke31 on 2010-01-03T22:38:00.000Z:

[Former user]

Comment # 6 originally posted by westonlast on 2010-01-03T23:16:17.000Z:

The version before the audio changes has much more consistent (and not scratchy) audio. I really think Zombies Ate My Neighbors mucking up other games is a separate issue.

[Former user]

Comment # 7 originally posted by ekeeke31 on 2010-01-04T14:24:00.000Z:

I still need more infos:

1/ does it still happen when "High Quality FM" is disabled ? 2/ is it indeed solved by returning to the menu ? reseting ? reloading the game ? 3/ be more precise: what do you mean by "more consistent audio" ? Don't get fooled by the revision changelog, the changes I made only brings a very tiny adjustment for accuracy purpose and for later changes, there is no way it could be noticeable by human ears :-)

To me, the bug still happens with the same randomness in this version as in previous versions, some games have scratchy sound when being loaded after some other games and sometime they don't (ie I could not reproduce this bug two times in a row).

And it's the same scratchy sound when you load Castlevania after Zombies (which is ALSO a random issue and depends how much time you exacly wait before loading the other game), hence why I'm pretty sure it's the same and one issue: it's very likely that it's not a specific game issue or an issue in the emulation cores but rather something wrong in the mixing or resampling audio engine.

It might also be caused by how Wii Audio DMA playback is configured: to keep video & audio perfectly synchronized (i.e to avoid any sound hicup or video frameskipping), I don't render the same amount of audio samples per video frame but rather output an average number of samples. Maybe this cause some issues when changing games, I need to investigate.

[Former user]

Comment # 8 originally posted by westonlast on 2010-01-04T20:56:09.000Z:

Test results from version before audio changes (to avoid issue \#1):

issue \#1: The constant static (hiss?) of the audio that sometimes happens using the new version of the emulator with Phantasy Star II or other games doesn't occur. I think the audio change is noticeable.

issue \#2: The "Zombies bug" isn't limited to that game or even Konami games. Golden Axe exhibited the same buggy behavior. Some games, including Konami games Rocket Knight Adventures and Contra Hard Corps, are always fine when played alone. High Quality FM: Off still produces the issue.

Reproducing issue \#2: The first game that is played always sounds fine. Loading the same exact game again will produce the bug if it is one of the problem games. ex) Zombies Ate My Neighbors, Castlevania Bloodlines, Golden Axe, etc.

Once the bug has occurred, Hard Reset will fix the audio. If the bug occurs and a non-problem game (Ecco the Dolphin) is loaded without a Hard Reset, that game will also produce the bug.

I agree that issue \#2 likely has to do with the Wii audio system.

[Former user]

Comment # 9 originally posted by ekeeke31 on 2010-01-05T08:47:36.000Z:

I did not notice anything wrong or different in Phantasy Star 2 (just started a new game and played a while), maybe you have a savestate to share where it is more obvious ? Or a detailled description of where it happens ?

Thanks for the details about the "scratchy sound" bug: the fact it does not seems related to "High Quality FM" also helps. Could you try the same tests with Region forced to "EUR" (PAL) ? Some games will obviously refuse to boot because of region protection but you can try to change the region after the game is started and see if it changes something.

[Former user]

Comment # 10 originally posted by westonlast on 2010-01-06T02:09:33.000Z:

Only a certain revision of Phantasy Star II (English, NTSC) exhibited the static (1989, ROM doesn't have revision number or any tags at all). It happens right at the title screen with r398.

[Former user]

Comment # 11 originally posted by ekeeke31 on 2010-01-06T09:22:46.000Z:

[Former user]

Comment # 12 originally posted by ekeeke31 on 2010-01-06T20:35:16.000Z:

I tried again with all known revisions of PSII but did not notice any issue or scratchy sound at title screen. I tested against Kega and the output is identical.

I also figured the "scratchy audio" bug does not happen when the TV Mode is forced to 50Hz (or the game forced to run in PAL mode), so it definitively has something to do with the audio sync method used in NTSC/60Hz mode.

[Former user]

Comment # 13 originally posted by westonlast on 2010-01-07T03:04:37.000Z:

Reproducing Issue1: (r398) 1. Load Ecco the Dolphin (NTSC) 2. Listen to the scratchy audio. Note that it is different than the crackly audio from Issue2. Perhaps Issue1 compounds Issue2. 3. Reloading/Hard Reset does not fix the scratchiness. 4. Load some version of Phantasy Star II (NTSC) immediately afterwards 5. Loading Ecco and then Phantasy Star II may take some tries to reproduce the bug, but when it happens it's very loud hiss/static.

[Former user]

Comment # 15 originally posted by ekeeke31 on 2010-01-07T13:23:59.000Z:

I didn't notice any scratchy audio after loading these 2 games, tried to reload them a bunch of time in this order to reproduce your issue but nothing. Are you sure you just didn't set the volume too loud in order to listen to possible audio "imperfections" and your TV setup can not handle it ? Because nothing is wrong here on my side, music is just fine :/

Anyway, I'm not sure to understand the difference between "crackly" and "scratchy" audio here, seems to me there is still one and single bug that affects some games, that's all. Maybe you could try to do some kind of video capture so that I can notice the issue, but otherwise, there is nothing I can do about "issue \#1" and I will concentrate myself fixing "issue \#2".

[Former user]

Comment # 17 originally posted by westonlast on 2010-01-08T01:22:37.000Z:

2: (crackle, separated) http://www.mediafire.com/?4wdidygjn4w Notice the little one right at the beginning of Ecco. Castlevania's title screen after Zombies is the worst.

1: (scratchy hiss/static/etc., constant) http://www.mediafire.com/?zuh322vjntm Got about three different variants of the audio issue. Ecco was hairy. A couple of the short Phantasy Star II segments were perfect (and thus short.) Phantasy Star II at the end is the real show.

[Former user]

Comment # 18 originally posted by westonlast on 2010-01-08T01:24:44.000Z:

Oh, and sorry about the noise. It must be the integrated sound card, because the headphone jack on the stereo does not sound that bad. I didn't want to alter the results.

[Former user]

Comment # 19 originally posted by ekeeke31 on 2010-01-08T11:39:44.000Z:

Can you point me the exact time where Ecco sounds wrong ? I don't notice anything here. I can hear the weird stuff at the end on Phantasy Star 2 but it seems to me it VERY random as you reloaded it a bunch of time before it would happen. Did not notice anything wrong in the sound before that other than usual noise that are probably releated to your TV output . Care to point me the exact times where it sounds wrong according to you ?

The other issue is the usual one that I can reproduce myself so nothing new about that one. The crackling noise on Ecco is from your TV, I don't have this on my setup.

[Former user]

Comment # 20 originally posted by ekeeke31 on 2010-01-08T11:45:28.000Z:

I should also note that I tried the same sequence (2nd recording) on my side and did not notice ANY of this sound artefact.

[Former user]

Comment # 21 originally posted by westonlast on 2010-01-09T05:40:06.000Z:

I assure you it's not my TV (well, because the audio doesn't pass through the TV) or my audio setup (Sony stereo receiver). This only happens in Genesis Plus GX while playing games.

This is the r398 OGG layout:

E1 -- P1 -- E2 -- P2 -- P3 -- P4 -- P5 -- P6

E1: very quiet, constant scratching; same little pop at beginning (from issue \#2) P1: high-pitched hum E2: very quiet, constant scratching P2: perfect P3: perfect P4: quiet hiss that contains changing pitches P5: perfect P6: loud hiss

I hope your headphones/speakers can reproduce these subtleties. Listen very carefully. :)

[Former user]

Comment # 22 originally posted by ekeeke31 on 2010-01-09T15:42:33.000Z:

Ok, I can hear the sound defects you are mentionning. The problem is that I could not reproduce this on my console, no matter how many time I try the exact same sequence.

[Former user]

Comment # 23 originally posted by westonlast on 2010-01-09T17:20:46.000Z:

Now that I have returned to college, I won't be able to test for a few months.

[Former user]

Comment # 24 originally posted by ekeeke31 on 2010-01-12T10:10:04.000Z:

Ecco's crackly sound in the intro is definitively there, guess I did not wait enough on title screen before. It is indeed a constant issue and should be fixed in future revisions. Note that it does not happen when setting TV Mode to 50Hz or forcing game region to EUR so it's definitively something in the audio backend, even if it's not similar than the "Castlevania" sound bug which is random and not game specific.

I could not reproduce the other issue with PSII, tried to load both revisions more than 10 times and always got perfect sound. It could be related to the 'Castlevania" bug for its randomness and effect or maybe I accidentally fixed it in my current revision (not commited yet).

[Former user]

Comment # 25 originally posted by ekeeke31 on 2010-01-24T11:43:14.000Z:

I've completely rewrote the sound processing and mixing part which should be now more accurate and avoid any sample skipping or lag. All scratching issues seem fiwed so far, at least I could not reproduce them anymore.

[Former user]

Comment # 26 originally posted by ekeeke31 on 2010-05-29T19:57:43.000Z: