MonoTouch application is crashing when returning from the background

I have a MonoTouch application that has an annoying bug and I don't know how to go about resolving it. The problem seems to occur when the application has been in the background for a considerable amount of time (a couple of hours, for example) and then you return to the application. Upon returning from the background, the application will work for a short period (about 10 seconds) and then it freezes up completely and none of the tabs, buttons, etc respond. After another 10 seconds or so, the application is killed by iOS. In the crash log, I see the following reported:

<appname> failed to resume in time

The annoying thing with this bug开发者_如何学运维 is that it never seems to occur when I am testing with the debugger; I run the application in debug mode and test it for ages without any problem. I also send it to the background and return without any problem. So, so far it only seems to occur when the application has been in the background for a long time... and it happens at different points in the application, never the same point. Does anyone have any idea what could be happening and how I would go about debugging a problem like this? Thanks.

Your app is probably doing something that takes longer than 10 seconds when you come back from background. iOS forces you to return within that predetermined period, or it'll kill your app for "misbehaving".

Your computer is thousands of times faster than the device. That's why you only see the issue in the simulator.

I would check your AppDelegate class to see what's happening in the WillEnterForeground method, that could be taking so long.