ModPlug + jBridge + Kontakt 3 crackling even under really light load.

shableep · May 28, 2011, 15:13:53

When I found jBridge I was pretty excited I could use it to get around the memory limitations of ModPlug. But for some reason I get constant crackling no matter how heavy or light the load. When I use Kontakt without jBridge, everything seems to work fine.

I was using on-board audio + Asio4All and thought my on-board audio might be the cause. So I got a Creative X-FI (not great, I know) and things seem to have actually gotten worse, even with the latest drivers.

Then I thought it might be jBridge specific. But I tested the same jBridge + Kontakt 3 setup in Renoise and it worked without a hitch.

here's what it sounds like. 1st scale jBridge+Kontakt. 2nd scale just Kontakt.
http://www.craigalbert.com/jbridge-sound-test.mp3

anyone know what might be causing this?

my specs:
Windows 7 (64-bit)
Intel Q6600 Quad Core 2.4ghz
4gb RAM
120gb SSD
Creative X-Fi Titanium

LPChip · May 28, 2011, 17:47:40

Try increasing the buffersize (aka latency)

shableep · May 28, 2011, 19:10:29

I did try that. And actually... changing the buffer size seems to just change the tone of the crackling.

It's almost as if there's some kind of clipping at the end of the buffer so it just makes the clipping sound at the rate of the buffer size. I have no idea if that's how the buffer works, but just a thought.

Here's what it sounds like at different buffer lengths:

200ms: http://www.craigalbert.com/jbridge-sound-test-200ms.mp3
50ms: http://www.craigalbert.com/jbridge-sound-test-50ms.mp3
30ms: http://www.craigalbert.com/jbridge-sound-test-30ms.mp3
10ms: http://www.craigalbert.com/jbridge-sound-test-10ms.mp3

Saga Musix · May 28, 2011, 20:06:11

Have you tried the alternative kx drivers for your soundcard? I've had similar problems when using ASIO4All on my soundcard (not with OpenMPT, though) and it was driving me nuts, the only solution was to use the native drivers of my soundcard for recording (which I wanted to avoid in this case so I could use native ASIO in OpenMPT and ASIO4All for recording simultaneously).

shableep · May 29, 2011, 06:43:47

Just checked the KX site, and it looks like X-Fi cards are actually not supported. =\

And yeah, I have tried native ASIO, Asio4All, and DirectSound. The results end up sounding different, but not really better.

I wonder what jBridge is doing that ModPlug doesn't like since Kontakt seems to work pretty well on it's own. I also tested this jBridge setup under VSTHost and things sounded good, even under heavy load. Any ideas what problems a bridged plugin might be causing?

LPChip · May 29, 2011, 16:18:24

I use different drivers too. They're creative labs drivers, but altered. I could upload it for you and send you a link, if interested.

Christofori · May 30, 2011, 11:06:10

You COULD also check the latency settings of your PCI Bus with 'PCI Latency Tool 3' available (currently) here: http://downloads.guru3d.com/download.php?det=951 -- but as I haven't looked your card up and am not familiar with it, I don't know the interface type.. this (as far as I know) only works with PCI cards (NOT PCI express) and not firewire/usb controlled cards directly (although read on if your card is fw/usb as there is still something you can try).

Once you load the tool, you'll see the devices that are plugged into your PCI slots. If you see everything is set to '0' then set your sound card's value to a higher number (perhaps 32 or 64 -- doesn't have to match the card's latency setting, and I don't even know if it's preferred for it to..) -- this will force your system to buffer (wait, basically, for x miliseconds IIRC.. x being the value you specify... before releasing bus control to the other devices). If your sound card is USB or firewire then you need it's latency buffer to be reset as described above, as those kinds of cards aren't listed in the tool (since they're not plugged directly into the PCI bus). But increasing the controller's latency on the bus WILL make a difference if this is what is causing your problems.

This doesn't even require a restart; you can tweak it to see if it helps, and then immediately test and see. Not sure it will, but it very well could if the drivers don't seem to.

Hope this helps!

shableep · May 30, 2011, 15:28:27

Quote from: LPChip on May 29, 2011, 16:18:24
I use different drivers too. They're creative labs drivers, but altered. I could upload it for you and send you a link, if interested.

They'd work with the Creative X-Fi? That'd be worth a try.

Quote from: christofori on May 30, 2011, 11:06:10
this (as far as I know) only works with PCI cards (NOT PCI express)

My card is actually PCE-e =\

LPChip · May 30, 2011, 16:06:31

Quote from: shableep on May 30, 2011, 15:28:27
Quote from: LPChip on May 29, 2011, 16:18:24
I use different drivers too. They're creative labs drivers, but altered. I could upload it for you and send you a link, if interested.

They'd work with the Creative X-Fi? That'd be worth a try.

Yes they do. I own a Creative X-Fi Elite Pro myself. They are creative drivers, but modified in such way that they actually work.

shableep · May 31, 2011, 06:09:13

So I tried those drivers you sent over, LPChip, and it looks like I'm still in the same situation. But thanks for sendin' those.

I did try this same jBridge + Kontakt setup in 2 different programs with no issues. In VSTHost I set the buffer to 90ms and loaded up enough samples to fill 300mb of ram. Then I tried a stress test with 400 voices playing at the same time. And there were no issues, no crackling. In ModPlug, I get the continuous crackling even with only 1-4 voices playing at the same time. So the issue doesn't seem to be my sound card. There's either something jBridge doesn't like about ModPlug, or ModPlug isn't taking kindly to jBridge.

I kinda wanna see if this is a ModPlug issue or not so I can let the author of jBridge know if he's got some compatibility issues he should check out.

LPChip · May 31, 2011, 07:32:58

If my memory serves me right, Kontakt3 has options for cpu usage etc. Try turning them down to a single cpu (if there's multicore support) and less polyphony.

shableep · June 02, 2011, 03:30:43

Right now in the test mp3 you heard, there is a max of 4 voices at one time and the CPU load never goes above 7%. I did try switching it to single-core mode and it didn't seem to make things any better. Are there sometimes problems with multi-core processors and Modplug?

And I just tested jBridge + Kontakt in Sonar X1 and everything sounded clear.

So what do you guys think?... Is this a bug?

And in case some of you wanna test it out on your own systems, here's some download links:
Kontakt 3 Demo
jBridge Demo

Saga Musix · June 02, 2011, 09:35:09

Quote from: shableep on June 02, 2011, 03:30:43Are there sometimes problems with multi-core processors and Modplug?

no.

Saga Musix · April 01, 2012, 16:12:57

http://bugs.openmpt.org/view.php?id=138#c679