# Weird GarageBand (iOS) keyboard issue

**URL:** <https://forum.juce.com/t/weird-garageband-ios-keyboard-issue/55238>\
**Category:** MacOSX and iOS\
**Created:** [March 4, 2023, 6:00am UTC](https://forum.juce.com/t/weird-garageband-ios-keyboard-issue/55238 "2023-03-04T06:00:59Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![pizzafilms](https://sea2.discourse-cdn.com/flex026/user_avatar/forum.juce.com/pizzafilms/32/562_2.png) [@pizzafilms](https://forum.juce.com/u/pizzafilms)\
**Post date:** [March 4, 2023, 6:00am UTC](https://forum.juce.com/t/weird-garageband-ios-keyboard-issue/55238/1 "2023-03-04T06:00:59Z")

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After a bit of beta testing, it seems that my AUv3 plugin only responds to every 16th note pressed on GarageBand’s keyboard. Press a key on GB’s keyboard, it plays, then play 15 more…nothing, then you hear the next one…and on and on. Almost like it’s cycling through the MIDI channels. It’s the strangest thing.

It works properly in AUM.

It works properly with a MIDI keyboard.

it’s only in GarageBand.

But get this…there are a couple of other 3rd party plugins that respond THE SAME WAY in GarageBand…but properly in AUM as well…and I’m fairly certain that those other plugins are using JUCE.

Anyone seen anything like this?

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**Author:** ![masshacker](https://sea2.discourse-cdn.com/flex026/user_avatar/forum.juce.com/masshacker/32/650_2.png) [@masshacker](https://forum.juce.com/u/masshacker)\
**Post date:** [March 4, 2023, 12:27pm UTC](https://forum.juce.com/t/weird-garageband-ios-keyboard-issue/55238/2 "2023-03-04T12:27:14Z")

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Unfortunately, yes.  
It’s a bug in GarageBand, which basically makes all AUv3 synths behave as if they were supporting the MPE protocol, even when that’s not the case. There’s a specific callback to tell the host about this and JUCE is implementing it correctly. I’m away from my computer now so I don’t remember its name atm.  
Sigh.

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**Author:** ![pizzafilms](https://sea2.discourse-cdn.com/flex026/user_avatar/forum.juce.com/pizzafilms/32/562_2.png) [@pizzafilms](https://forum.juce.com/u/pizzafilms)\
**Post date:** [March 4, 2023, 4:35pm UTC](https://forum.juce.com/t/weird-garageband-ios-keyboard-issue/55238/3 "2023-03-04T16:35:42Z")

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Thank you for confirming this. I thought I was losing it.

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**Author:** ![luza](https://sea2.discourse-cdn.com/flex026/user_avatar/forum.juce.com/luza/32/18565_2.png) [@luza](https://forum.juce.com/u/luza)\
**Post date:** [May 20, 2024, 2:45pm UTC](https://forum.juce.com/t/weird-garageband-ios-keyboard-issue/55238/4 "2024-05-20T14:45:07Z")

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Hey guys,  
I’m having the same problem!

I’ve overridden AudioProcessor::supportsMPE() for my audio processor but it still cycles through midi channels 1-16.  
Any ideas? How did you guys fix it in the end?  
Is there something else I need to override?

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**Author:** ![masshacker](https://sea2.discourse-cdn.com/flex026/user_avatar/forum.juce.com/masshacker/32/650_2.png) [@masshacker](https://forum.juce.com/u/masshacker)\
**Post date:** [May 29, 2024, 12:54pm UTC](https://forum.juce.com/t/weird-garageband-ios-keyboard-issue/55238/5 "2024-05-29T12:54:15Z")

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Hey @luza, unfortunately I never found a workaround for this issue. Maybe filing a bug report with Apple could be helpful.

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**Author:** ![mathieudemange](https://sea2.discourse-cdn.com/flex026/user_avatar/forum.juce.com/mathieudemange/32/13333_2.png) [@mathieudemange](https://forum.juce.com/u/mathieudemange)\
**Post date:** [August 30, 2026, 9:21pm UTC](https://forum.juce.com/t/weird-garageband-ios-keyboard-issue/55238/6 "2026-08-30T21:21:56Z")

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Hopefully @mfritze could help us here?