[BUG] Loading certain A1 models after A2 models can cause audio crackling / dropouts

[benediktadams]

Hi,

we discovered a hard-to-reproduce issue, where certain A1 models will not play correctly when loaded right after certain other A2 models. Re-instantiating the plugin (prepareToPlay call) will resolve the issue.

We discovered this on our own implementation of the NAM Core (which uses none of the Gateway plugin harness), and verified it on Gateway, which leads us to believe the issue lies with the NAM Core itself.

See the following video reproducing the issue on Gateway.
https://github.com/user-attachments/assets/e36ccd2e-7875-4f88-9366-a179ecb721d2

Additionally you can find Models used on video.zip here.

Please let me know if you need any additional information.

[sdatkinson]

Care to clarify this?

We discovered this on our own implementation of the NAM Core (which uses none of the Gateway plugin harness), and verified it on Gateway, which leads us to believe the issue lies with the NAM Core itself.

NAM Core is a DSP library; Gateway is a private fork of NeuralAmpModelerPlugin...what's the "Gateway plugin harness" that this library uses? And are you saying that this can be observed without putting this library in a plugin? Would a test that just instantiates a model a bunch of times and keep checking the predictions maybe expose the bug?

Thanks for the video & models; I'll get to them later.

[benediktadams]

Yeah sorry for the confusion.

We’re using the NAM core in our own plugin, where we discovered the issue. This plugin uses no code from the NeuralAmpModelerPlugin, but is a custom juce implementation around the NAM core.

We used Gateway to confirm that the issue is not in our juce plugin code, but that it happens (probably) in the NAM Core. That’s what the video shows.

Hope that helps