Hi timski,
Thank you for your message.
Unfortunately, we’re not equipped with ToneStack, to give it a smoke check.
Please note that Inter-App Audio comes with many limitations, summarized on our dedicated Limitations of Inter-App Audio article.
In addition, Apple already announced, that IAA is planned to be discontinued.
It might make sense to watch out for Audio Unit compatible apps, which is Apple’s successor of Inter-App Audio and comes with more flexible options.
Please get in touch with Yonac to let them know about the issue.
If required, we’re at hand to exchange with them.
Hope that helps!
Best,
Lars