Not sure if this is helpful or not, but decided to let you know in case you can make any sense out of it.
I got this crash. Haven't seen it before or after - just once.
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Subtype: KERN_INVALID_ADDRESS at 0x0000001c
Triggered by Thread: 0
Thread 0 Crashed:
0 libAVFAudio.dylib 0x2d6ccc48 -[AVAudioPlayer stop] + 36
1 libAVFAudio.dylib 0x2d6cbd16 -[AVAudioPlayer(AVAudioPlayerPriv) finishedPlaying:] + 26
2 Foundation 0x2f102036 __NSThreadPerformPerform + 382
3 CoreFoundation 0x2e6ea188 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 12
4 CoreFoundation 0x2e6e9656 __CFRunLoopDoSources0 + 202
5 CoreFoundation 0x2e6e7e4a __CFRunLoopRun + 618
6 CoreFoundation 0x2e652ce2 CFRunLoopRunSpecific + 518
7 CoreFoundation 0x2e652ac6 CFRunLoopRunInMode + 102
8 GraphicsServices 0x3334027e GSEventRunModal + 134
9 UIKit 0x30ef4a3c UIApplicationMain + 1132
10 Phyzzlets 0x0001ecd2 0x18000 + 27858
11 Phyzzlets 0x0001ec5c 0x18000 + 27740