Hi again! 😄
I have some good news! The audio issue has now been fixed in NiN10 3.1, so games made with BPCore-Engine now play with sound correctly.
That means Funkin' GBA now has working audio on iPhone, iPad, and even Apple Watch! 🎉
Also, if you're still okay with it, I'll be using Funkin' GBA for some App Store screenshots in the next update. I'll let you know as soon as they're published!
Thanks again for your support, and for creating such an awesome project! 😄