Game crashing on iOS after 3 second load of new scene. (How can I optimise loading)

Unity Engine
1

Hi guys, my game is crashing when I load between certain scenes on an iOS device . Here is a couple screenshots of the output from the Unity profiler showing the spikes.

This first one is from a main menu screen with an OnGUI function to another menu scene with an OnGUI function, so there are only textures in the gui and a 3d model of a character:

This second one is from that second menu scene to a large level with many objects:

http://cl.ly/2N1H2y0a0u27222a381c

What are the sort of the optimisations I need to be doing in order to reduce this and eliminate the crashing? This has only started happening recently, since I upgraded to 3.4 (perhaps this is to do with it?)

Thanks for any help you can provide me with!

Unity Answers post on same issue: http://answers.unity3d.com/questions/152753/game-crashing-on-ios-after-3-second-load-of-new-sc.html?viewedQuestions=145343

2

Also my texture memory spikes at around 35mb for the single loading frame. Although all my textures are 256*256 pixels with a couple being 512px (all compressed and pvrtc 4 bits)