Hmm, that is a doozy. I can’t think of any better solutions for the time being though.
I thought this might ruin the channel counts of synths but things seem to be ok (tried with Kontact 16-out).
What is the effect of not calling plugInOpcodeGetSpeakerArrangement?
The layout information will be lost for plug-ins that do not implement getPinProperties. In these cases, if your synth has 6 output channels, JUCE will not know if this is 5.1 surround, hexaphonic or 6.0 surround.
Ah ok. That’s actually fine for my use case 
What is the status of this bug? Turns out Helm is also affected by this. Commenting out the offending line was a workaround, but I don’t like having to modify JUCE code just to have a working build. Did that fix get moved from develop into master?
If you are using the latest version of JUCE (both master and develop), then Helm should not be affected by this bug.
Hi everyone, I wonder if someone has encountered this issue: I’m trying to build an Audio Unit plug-in which supports mono and stereo input, and from mono to 7.1 surround output. This is how I wrote it:
#ifndef JucePlugin_PreferredChannelConfigurations
bool Shuffling::isBusesLayoutSupported(const BusesLayout& layouts) const
{
#if JucePlugin_IsMidiEffect
ignoreUnused (layouts);
return true;
#else
if(layouts.getMainInputChannelSet()==AudioChannelSet::mono())
{
if (!layouts.getMainInputChannelSet().isDisabled())
{
if (!layouts.getMainOutputChannelSet().isDisabled())
{
if (layouts.getMainOutputChannelSet()==AudioChannelSet::mono())
return true;
else if (layouts.getMainOutputChannelSet()==AudioChannelSet::stereo())
return true;
else if (layouts.getMainOutputChannelSet()==AudioChannelSet::quadraphonic())
return true;
else if (layouts.getMainOutputChannelSet()==AudioChannelSet::create5point0())
return true;
else if(layouts.getMainOutputChannelSet()==AudioChannelSet::create5point1())
return true;
else if (layouts.getMainOutputChannelSet()==AudioChannelSet::create7point1())
return true;
else
return false;
}
else
return false;
}
else
return false;
}
if (layouts.getMainInputChannelSet()==AudioChannelSet::stereo())
{
if (!layouts.getMainInputChannelSet().isDisabled())
{
if (!layouts.getMainOutputChannelSet().isDisabled())
{
if (layouts.getMainOutputChannelSet()==AudioChannelSet::stereo())
return true;
else if (layouts.getMainOutputChannelSet()==AudioChannelSet::quadraphonic())
return true;
else if (layouts.getMainOutputChannelSet()==AudioChannelSet::create5point0())
return true;
else if(layouts.getMainOutputChannelSet()==AudioChannelSet::create5point1())
return true;
else if (layouts.getMainOutputChannelSet()==AudioChannelSet::create7point1())
return true;
else
return false;
}
else
return false;
}
else
return false;
}
return false;
#endif
}
#endif
However, the way the plug-in behaves depends on the constructor: if I start my plug-in with a stereo input like this:
Shuffling::Shuffling()
#ifndef JucePlugin_PreferredChannelConfigurations
: MyEffect(BusesProperties().withInput("Input", AudioChannelSet::stereo()).withOutput("Output", AudioChannelSet::stereo()))
#endif
the plug-in won’t support mono input with anything else than mono or stereo output, like shown in the auval analysis:
FORMAT TESTS:
Reported Channel Capabilities (explicit):
[1, 1] [1, 2] [2, 2] [2, 4] [2, 5] [2, 6] [2, 8]
Input/Output Channel Handling:
1-1 1-2 1-4 1-5 1-6 1-7 1-8 2-2 2-4 2-5 2-6 2-7 2-8 4-4 4-5 5-5 6-6 7-7 8-8
X X X X X X X
In: 1 , Out: 1
In: 1 , Out: 2
In: 1 , Out: 4
WARNING: Can Initialize Unit to un-supported num channels:InputChan:1, OutputChan:4
In: 1 , Out: 5
WARNING: Can Initialize Unit to un-supported num channels:InputChan:1, OutputChan:5
In: 1 , Out: 6
WARNING: Can Initialize Unit to un-supported num channels:InputChan:1, OutputChan:6
ca_require: ValidFormat(inScope, inElement, newDesc) InvalidFormat /Users/stagiaireprod/Desktop/Octave_Roulleau/GRm_vst_wrapper/Shuffling_test_AU/GRM_Tools_SRC/Common/au/CoreAudioUtilityClasses/AUBase.cpp:870
In: 1 , Out: 8
WARNING: Can Initialize Unit to un-supported num channels:InputChan:1, OutputChan:8
In: 2 , Out: 2
In: 2 , Out: 4
In: 2 , Out: 5
In: 2 , Out: 6
ca_require: ValidFormat(inScope, inElement, newDesc) InvalidFormat /Users/stagiaireprod/Desktop/Octave_Roulleau/GRm_vst_wrapper/Shuffling_test_AU/GRM_Tools_SRC/Common/au/CoreAudioUtilityClasses/AUBase.cpp:870
In: 2 , Out: 8
ca_require: ValidFormat(inScope, inElement, newDesc) InvalidFormat /Users/stagiaireprod/Desktop/Octave_Roulleau/GRm_vst_wrapper/Shuffling_test_AU/GRM_Tools_SRC/Common/au/CoreAudioUtilityClasses/AUBase.cpp:870
ca_require: ValidFormat(inScope, inElement, newDesc) InvalidFormat /Users/stagiaireprod/Desktop/Octave_Roulleau/GRm_vst_wrapper/Shuffling_test_AU/GRM_Tools_SRC/Common/au/CoreAudioUtilityClasses/AUBase.cpp:870
ca_require: ValidFormat(inScope, inElement, newDesc) InvalidFormat /Users/stagiaireprod/Desktop/Octave_Roulleau/GRm_vst_wrapper/Shuffling_test_AU/GRM_Tools_SRC/Common/au/CoreAudioUtilityClasses/AUBase.cpp:870
ca_require: ValidFormat(inScope, inElement, newDesc) InvalidFormat /Users/stagiaireprod/Desktop/Octave_Roulleau/GRm_vst_wrapper/Shuffling_test_AU/GRM_Tools_SRC/Common/au/CoreAudioUtilityClasses/AUBase.cpp:870
ca_require: ValidFormat(inScope, inElement, newDesc) InvalidFormat /Users/stagiaireprod/Desktop/Octave_Roulleau/GRm_vst_wrapper/Shuffling_test_AU/GRM_Tools_SRC/Common/au/CoreAudioUtilityClasses/AUBase.cpp:870
ca_require: ValidFormat(inScope, inElement, newDesc) InvalidFormat /Users/stagiaireprod/Desktop/Octave_Roulleau/GRm_vst_wrapper/Shuffling_test_AU/GRM_Tools_SRC/Common/au/CoreAudioUtilityClasses/AUBase.cpp:870
In: 2 , Out: 2
ca_require: IsStreamFormatWritable(inScope, inElement) NotWritable /Users/stagiaireprod/Desktop/Octave_Roulleau/GRm_vst_wrapper/Shuffling_test_AU/GRM_Tools_SRC/Common/au/CoreAudioUtilityClasses/AUBase.cpp:875
This will also be the case if I switch from stereo to mono input in the constructor: the plug-in won’t support stereo output with anything else than stereo output, while all the mono input configurations seem to work fine.
The problem doesn’t occur when I define the JucePlugin_PreferredChannelConfigurations macro instead.
I tried that with Juce version 4.3.1, 5.0.1 and 5.0.2 but nothing changes. Does anyone kwon how to work my way around that?
Thanks for the report. I was able to reproduce this bug and will report back once it’s fixed.
This should be fixed on develop now.
Works like a charm ! Thanks a lot fabian
