Doesn't seem related to intelligent mode, the thread is saying cards with unbuffered MPU-401 will drop data with the poorly written MIDI driver in Sam & Max. People are usually talking about SB cards in that context but someone else says it happens on a CMI card and I guess it also affects your YMF card.

No-one seems to have offered a solution other than switching to a card with MPU-401 buffering. For what it's worth, the PicoGUS seems to work fine with Sam & Max.

Intelligent mode was available with the original MPU-401 ISA card and breakout box, it had some more advanced features. Most card and games use UART mode which is just a simple MIDI data stream.

NeoG_ wrote on 2026-02-25, 12:47:

Doesn't seem related to intelligent mode, the thread is saying cards with unbuffered MPU-401 will drop data with the poorly written MIDI driver in Sam & Max. People are usually talking about SB cards in that context but someone else says it happens on a CMI card and I guess it also affects your YMF card.

No-one seems to have offered a solution other than switching to a card with MPU-401 buffering. For what it's worth, the PicoGUS seems to work fine with Sam & Max.

Intelligent mode was available with the original MPU-401 ISA card and breakout box, it had some more advanced features. Most card and games use UART mode which is just a simple MIDI data stream.

Okay, thanks for the insight. Hmm. I have added the PicoGUS on my list of components to get. Did I also read that it makes it possible to use redbook audio CD images in DOS...? Or am I misunderstanding? And if it does, how exactly does that work? Thanks.

Also, I read 'CMI' as Curse of Monkey Island. 🤣

I will second the PicoGus suggestion. My SC-55 + PicoGus has been glitch-free. While I haven't tried Sam & Max, and it shouldn't require intelligent mode, MPU-401 implementation was a very mixed bag on vintage sound cards. The PicoGus will coexist with other ISA sound cards without a hassle, so it is worth getting, even if you don't need its other features/modes.

Out of curiosity, which Yamaha OPL3 card? I have a YMF718-S that has always worked great, but my card has a significantly different design than all of the A151 "Audition 32" cards that are common, and I have seen a few hanging-note complaints.

DustyShinigami wrote on 2026-02-25, 12:59:

Okay, thanks for the insight. Hmm. I have added the PicoGUS on my list of components to get. Did I also read that it makes it possible to use redbook audio CD images in DOS...? Or am I misunderstanding? And if it does, how exactly does that work? Thanks.

Yes, emulation for Panasonic/MKE CD-ROM was added, including redbook audio playback:
https://github.com/polpo/picogus/wiki/CD%E2%8 … 90ROM-Emulation

The CD images are read from a USB memory stick, and presented via MKE CD-ROM driver. The audio bitstream is fed to the audio DAC on the PicoGus. There are some speed limitations, but really impressive emulation from a RP2040, and such an awesome project overall. The PicoIDE project being developed and crowdfunded by the same person, and I bet will be a great option for ATAPI optical CD images.

Fazeshift wrote on 2026-02-25, 18:11:

I will second the PicoGus suggestion. My SC-55 + PicoGus has been glitch-free. While I haven't tried Sam & Max, and it shouldn't […]
Show full quote

I will second the PicoGus suggestion. My SC-55 + PicoGus has been glitch-free. While I haven't tried Sam & Max, and it shouldn't require intelligent mode, MPU-401 implementation was a very mixed bag on vintage sound cards. The PicoGus will coexist with other ISA sound cards without a hassle, so it is worth getting, even if you don't need its other features/modes.

Out of curiosity, which Yamaha OPL3 card? I have a YMF718-S that has always worked great, but my card has a significantly different design than all of the A151 "Audition 32" cards that are common, and I have seen a few hanging-note complaints.

DustyShinigami wrote on 2026-02-25, 12:59:

Okay, thanks for the insight. Hmm. I have added the PicoGUS on my list of components to get. Did I also read that it makes it possible to use redbook audio CD images in DOS...? Or am I misunderstanding? And if it does, how exactly does that work? Thanks.

Yes, emulation for Panasonic/MKE CD-ROM was added, including redbook audio playback:
https://github.com/polpo/picogus/wiki/CD%E2%8 … 90ROM-Emulation

The CD images are read from a USB memory stick, and presented via MKE CD-ROM driver. The audio bitstream is fed to the audio DAC on the PicoGus. There are some speed limitations, but really impressive emulation from a RP2040, and such an awesome project overall. The PicoIDE project being developed and crowdfunded by the same person, and I bet will be a great option for ATAPI optical CD images.

Thank you for the info. And that's awesome that redbook audio playback is supported. 😀 I have quite a few questions though. ^^; Do CD images have to be played via a USB memory stick or can they not be read from the HDD? Is it any USB stick formatted to FAT32? Or does the card come with a specially designed one? I take it a firmware needs to be installed first? Does it require Windows/DOS drivers? And finally, I take it it doesn't require an audio cable to be connected from the card to the CD-ROM?

It sounds like an awesome card; I'll definitely have to get one. 😀

I'm using a Yamaha YMF719E-S. Not really had an issues with it, either. Except for this hanging note in Sam & Max and Simon 2.

Yes they have to be on a USB stick plugged into the card, any decent quality USB stick formatted as FAT32 should work. I use a Sandisk FIT 128GB because it's small and doesn't poke out too much. I use the USB stick for DOS disc images, and use alcohol 120% with images on an SD-IDE adapter for windows disc images.

The PicoGUS will output redbook CD audio through the audio jack on the rear of the card - You would need to find some way to mix that into the rest of the audio your system is producing. I modified my SB Live card to have two line inputs inputs on the rear and use it to mix everything together.

Drivers for DOS and windows are available on the PicoGUS site, it uses a creative driver. I don't use the PicoGUS disc emulation in windows, it's too slow for windows games so I just use it only in MS-DOS mode for DOS games.

NeoG_ wrote on 2026-02-25, 23:04:

Yes they have to be on a USB stick plugged into the card, any decent quality USB stick formatted as FAT32 should work. I use a Sandisk FIT 128GB because it's small and doesn't poke out too much. I use the USB stick for DOS disc images, and use alcohol 120% with images on an SD-IDE adapter for windows disc images.

The PicoGUS will output redbook CD audio through the audio jack on the rear of the card - You would need to find some way to mix that into the rest of the audio your system is producing. I modified my SB Live card to have two line inputs inputs on the rear and use it to mix everything together.

Drivers for DOS and windows are available on the PicoGUS site, it uses a creative driver. I don't use the PicoGUS disc emulation in windows, it's too slow for windows games so I just use it only in MS-DOS mode for DOS games.

Right, I see. Thanks. Would mixing work in a way I've already done? Daisy-chaining the cards? Using MPXPlayer? Or is this a case of needing a proper sound mixer?

DustyShinigami wrote on 2026-02-25, 23:45:

Right, I see. Thanks. Would mixing work in a way I've already done? Daisy-chaining the cards? Using MPXPlayer? Or is this a case of needing a proper sound mixer?

It's another audio cable you would need to figure out what to do with, for example there won't be another stereo input on the back of the SB Live card. you could use the line input on the YMF card, but that means it will only work with both the YMF card Live card are active. That's why I modified my Live card to have an additional stereo input on the back of the card.

Or you could just go to an external mixer.

NeoG_ wrote on 2026-02-25, 23:56:

DustyShinigami wrote on 2026-02-25, 23:45:

Right, I see. Thanks. Would mixing work in a way I've already done? Daisy-chaining the cards? Using MPXPlayer? Or is this a case of needing a proper sound mixer?

It's another audio cable you would need to figure out what to do with, for example there won't be another stereo input on the back of the SB Live card. you could use the line input on the YMF card, but that means it will only work with both the YMF card Live card are active. That's why I modified my Live card to have an additional stereo input on the back of the card.

Or you could just go to an external mixer.

Hmm. Sadly, the line input on the YMF card is in use. By the SC-55.

DustyShinigami wrote on Yesterday, 00:14:

Hmm. Sadly, the line input on the YMF card is in use. By the SC-55.

There is a line input on the SC-55, how far do you want to daisy chain the audio 🤔

NeoG_ wrote on Yesterday, 00:17:

DustyShinigami wrote on Yesterday, 00:14:

Hmm. Sadly, the line input on the YMF card is in use. By the SC-55.

There is a line input on the SC-55, how far do you want to daisy chain the audio 🤔

The line port is in use by the MIDI cable. Or have I had it plugged into the wrong one this whole time...? ^^; Should it be in OUT instead?

But not very far. The SC-55 is on top of my subwoofer, which is sat next to my case. So the cards and canvas are in close proximity to each other.

Got curious and just checked this. I let the intro run and then let the game sit for a few minutes in the opening office scene. I did NOT experience any hanging notes. Is there something else I have to do to induce the hanging notes?

To clarify my setup:

Pentium MMX 200 MHz (slowed down with Setmul to ~486 DX2 speeds)
Yamaha YMF-719 (for MIDI output)
Sound Blaster 16 CT2950 w/ OPL chip (for everything else)

I have a WavetablePi on the YMF-719 emulating GM. I'm using Unisound to set up the soundcards. I'm using the original CD-ROM talkie version of Sam & Max and I don't have any patches for the game installed.

Just to clarify: I enabled General MIDI for music in the Sam & Max setup, and the game was definitely playing General MIDI music.

jh80 wrote on Yesterday, 11:04:

Got curious and just checked this. I let the intro run and then let the game sit for a few minutes in the opening office scene. […]
Show full quote

Got curious and just checked this. I let the intro run and then let the game sit for a few minutes in the opening office scene. I did NOT experience any hanging notes. Is there something else I have to do to induce the hanging notes?

To clarify my setup:

Pentium MMX 200 MHz (slowed down with Setmul to ~486 DX2 speeds)
Yamaha YMF-719 (for MIDI output)
Sound Blaster 16 CT2950 w/ OPL chip (for everything else)

I have a WavetablePi on the YMF-719 emulating GM. I'm using Unisound to set up the soundcards. I'm using the original CD-ROM talkie version of Sam & Max and I don't have any patches for the game installed.

Just to clarify: I enabled General MIDI for music in the Sam & Max setup, and the game was definitely playing General MIDI music.

But were you using a Roland SC-55? That's what gets affected. I have General MIDI enabled in the setup, too, but it plays through my sound canvas. The issue triggers during the intro, before the credits start.

jh80 wrote on Yesterday, 11:04:

Got curious and just checked this. I let the intro run and then let the game sit for a few minutes in the opening office scene. I did NOT experience any hanging notes. Is there something else I have to do to induce the hanging notes?

If I'm not mistaken the YMF card is handling both the MIDI and digital sound, which begs the question if Dusty disables digital audio does that fix the hanging note issue

It shouldn't matter so much which MIDI synthesizer is being used if the MIDI data is being botched by the card

NeoG_ wrote on Yesterday, 11:39:

jh80 wrote on Yesterday, 11:04:

Got curious and just checked this. I let the intro run and then let the game sit for a few minutes in the opening office scene. I did NOT experience any hanging notes. Is there something else I have to do to induce the hanging notes?

If I'm not mistaken the YMF card is handling both the MIDI and digital sound, which begs the question if Dusty disables digital audio does that fix the hanging note issue

It shouldn't matter so much which MIDI synthesizer is being used if the MIDI data is being botched by the card

I'll give it a try later and see what happens.

DustyShinigami wrote on Yesterday, 11:26:

But were you using a Roland SC-55? That's what gets affected. I have General MIDI enabled in the setup, too, but it plays through my sound canvas. The issue triggers during the intro, before the credits start.

As NeoG said and as indicated by the earlier thread, this is a problem with the sound card, not the SC-55. So presumably the bug should occur on any MIDI device.

NeoG_ wrote on Yesterday, 11:39:

If I'm not mistaken the YMF card is handling both the MIDI and digital sound, which begs the question if Dusty disables digital audio does that fix the hanging note issue

It shouldn't matter so much which MIDI synthesizer is being used if the MIDI data is being botched by the card

In my case, the YMF is only handling the MIDI. In the Sam & Max sound setup (advanced options), you can set independent devices for music and digital audio, so I've got the MIDI through the YMF and the digital audio through the SB16.

So, yes, it would be good for Dusty to try disabling digital audio (via advanced options; keep MIDI enabled) and see if the problem still happens.

Also, Dusty: What CPU/speed are you using? The MIDI sound test / game itself will crash the computer for me if I am running at 200 MHz.

jh80 wrote on Yesterday, 12:31:

As NeoG said and as indicated by the earlier thread, this is a problem with the sound card, not the SC-55. So presumably the bug […]
Show full quote

DustyShinigami wrote on Yesterday, 11:26:

But were you using a Roland SC-55? That's what gets affected. I have General MIDI enabled in the setup, too, but it plays through my sound canvas. The issue triggers during the intro, before the credits start.

As NeoG said and as indicated by the earlier thread, this is a problem with the sound card, not the SC-55. So presumably the bug should occur on any MIDI device.

NeoG_ wrote on Yesterday, 11:39:

If I'm not mistaken the YMF card is handling both the MIDI and digital sound, which begs the question if Dusty disables digital audio does that fix the hanging note issue

It shouldn't matter so much which MIDI synthesizer is being used if the MIDI data is being botched by the card

In my case, the YMF is only handling the MIDI. In the Sam & Max sound setup (advanced options), you can set independent devices for music and digital audio, so I've got the MIDI through the YMF and the digital audio through the SB16.

So, yes, it would be good for Dusty to try disabling digital audio (via advanced options; keep MIDI enabled) and see if the problem still happens.

Also, Dusty: What CPU/speed are you using? The MIDI sound test / game itself will crash the computer for me if I am running at 200 MHz.

I swapped my PIII out again for my PII. That's 233MHz. I can't get it lower than that. I've not encountered any crashes in-game though. But I do get a lock up if I try doing the MIDI sound test. However, I downloaded this patch, which fixed that problem. https://tgames.fr/progs-pc/general-midi-fix-s … ter-t12191.html

Before that, I did try disabling the L2 cache, but it didn't work.

jh80 wrote on Yesterday, 12:31:

So, yes, it would be good for Dusty to try disabling digital audio (via advanced options; keep MIDI enabled) and see if the problem still happens.

Yep, disabled the SB/speech so it’s just the music and the hanging note bug doesn’t happen.

It would be nice if someone can confirm but I think we have another case of a sound chip not being able to handle simultaneous digital audio and MPU-401 in some cases

They seem to be popping up now that everyone is using SC-55s and wave table cards

@jh80 Does your system allow the temporary configuation change to route digital audio to the YMF card?

I just checked using only the YMF-719 and I did not get any hanging notes.

I think this is a CPU speed-related issue, perhaps related to the patch Dusty is using.

Dusty: Can you try slowing down your CPU and not using the S&M patch?

I'm not familiar with disabling cache on a Pentium II, but a quick search suggests disabling both L1 and L2 on a Pentium II will put it in 386 speed territory, which might be enough to run S&M.