IL2CPP app freezing on iOS 9.1/9.2 (Unity 4.6.9p2, 4.7.0)

I’m developing on Unity3d pro 4.6.9f1, 4.6.9p2, 4.7.0
When I checked backend scripts using by ‘IL2CPP’. app freezing with GC_LOCK when call the ‘LoadLevel’.
i don’t know why. cause. it is well running before.
and it is strange. that when i choose backend scripts ‘mono 2.x’ it run well on device. no freeze !

my application called ‘Application.LoadLevel’ in coroutine method.

My Testing iOS Version is 9.1,9.2.
below is my log. after that log it is freezing.
and, when i debug stack. that show me . ‘GC_LOCK’ last trace of stack.

============================================================ LOG ============================================================
2015-12-18 21:37:45.253 loadevtest[1793:694646] → registered mono modules 0x101405dd0
→ applicationDidFinishLaunching()
→ applicationDidBecomeActive()
Requesting Resolution: 1334x750
Init: screen size 1334x750
Initializing Metal device caps
Initialize engine version: 4.7.0f1 (9c73fd3cda99)
UnloadTime: 6.725333 ms
Unloading 4 Unused Serialized files (Serialized files now loaded: 0 / Dirty serialized files: 0)

Unloading 662 unused Assets to reduce memory usage. Loaded Objects now: 1131.
Total: 15.516417 ms (FindLiveObjects: 0.092416 ms CreateObjectMapping: 0.133583 ms MarkObjects: 0.916791 ms DeleteObjects: 14.206583 ms)

UnloadTime: 32.123333 ms

I need your help as soon as possible u can… thanks.

4.6.9 f . worked correctly but, after add some resources and scripts
it doesn’t work !

We’ve sent bug report through our PC on last week and would you please check what’s going on there?