Audiokit: AKOperationEffect causes malloc error

[crashingbooth]

Someone posted about this on StackOverflow a few months back, but it probably belongs here.

I was getting odd error messages and crashing in my project in two places that used AKOperationEffect. Basically, I noticed that when I included an AKOperationEffect in the signal chain, the first call I made to AudioKit.start() would be okay, but any subsequent call produced an error message such as:

Could not find function called '\255\276\274\301ݺ@~'.
\255\276\274\301ݺ@~ returned an error.

And a subsequent call to AudioKit.stop() crashed the app:

AKOperationEffectIssue(9735,0x1156d1340) malloc: *** error for object 0x60400015c300: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug

Poking around in the View Memory Hierarchy debugger, I can see that the AKOperationEffectAudioUnit lingers around even after the AKOperationEffect reference is removed.

Here is a sample project demonstrating the problem:
https://github.com/crashingbooth/AKOperationEffectIssue

[aure]

You're pretty active on AudioKit, would you like to be part of the Slack group?

[crashingbooth]

I think I already am - I just haven't checked in since first joining a year or so ago.

[aure]

Just want to add that as I'm closing issues I can't act, I'm pushing this up the priority as I think I can fix it.

[aure]

This change fixes the project you sent over and I think its a fine change over all. There may be even more we can do to make operations more robust, but I'll call this a win for now.