Host scanning for plugin

Hi there,

haven't been here for quite a while, probably because juce just works as expected :-)

I just have one question. A client of mine complains about Logic Pro does always scan

my plugin on startup like it would do when it was freshly installed. Is this something I can 

change/fix or do I have to leave it to the mercy of the host?

Thanks for any hint in this regard.


Nobody can help with a hint?

A few weeks ago a tester and I had a similar behaviour of Logic with a plugin of mine. But he also experienced a 'plugin not passed' from time to time, so it might not be related to your case.

I additionally figured out that it did not always passed auval. With a ratio of approx 1 out of 30. The failure happend on the destruction of the plugin, memory access violation. The reason lied in an external sample rate conversion library. Since I'm not very fluent in pure C and already had an alternative implemented myself, I just got rid of it. I have not investigated any further.

Hi Samuel,

thanks for your reply.

It just turned out that Logic actually labels the version number to be invalid.

The plugin passes AU validation w/o problems but it seems that the version number is not corectly

set or something like this.



Well, it has to do with the version number. As the specs say, the AU version number must be

an 8-digit hex string like this 0x00040203 which should read in Logic  4.2.3 but if I put

that number in the Introjucer then it will convert into 0x40203.

For now I can define JucePlugin_VersionCode manually but would be nice to see a fix here.

The client just confirmed that it works with the manual change.


Thanks for the info! We'll look into this.

I am having an issue with a SSL plug-in, the new SSL Bus Compressor rescans every time Logic is opened. It turns out it is listing the plug-in version as invalid. Anyone know how to fix this?

What is your version number set to?

Has this ever been addressed? I have in my version number field in Projucer, but Logic says it has an invalid version number, and auval (although it passes validation) says it is version 2304.0.5. If I have to define JucePlugin_VersionCode “manually”, where would I do that? In the preprocessor definitions in the project settings? And would I only be allowed to define the version as 9.0.0, not (or whatever build # this is), since it needs to fit in 0x00090000 format?

On a related note, is there a way to automatically add the build number, and have that show up at least in the bundle’s GetInfo screen, even if we can’t use that in Logic and auval?


This would apply to all formats, not just AU (unless you are only building AU for that project, obviously).

If you want to define JucePlugin_VersionCode only when building an AU plugin, you can add the following to the user code section of the AppConfig.h header:

#if JucePlugin_Build_AU \
    && !JucePlugin_Build_VST \
    && !JucePlugin_Build_VST3 \
    && !JucePlugin_Build_AUv3 \
    && !JucePlugin_Build_RTAS \
    && !JucePlugin_Build_AAX \
    && !JucePlugin_Build_Standalone \
    && !JucePlugin_Build_Unity
 #define JucePlugin_VersionCode 0x00090000
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