Sorry, but this has to be said: Your evidence clearly implies that some code of your own creation is causing the problem. Yet you give only the barest hint as to what the code is. [a] I could offer a zillion guesses as to what is wrong with that code if I could type faster and was immortal. That would be a waste of my time, other readers' time, and your time. So, I await a better set of clues as to what went wrong. [a. The subset of "code" that uses the callback technique to do "things" is quite large, undoubtedly super-astronomically large. ] Another point: It is considered rude to repost the same inquiry under different thread titles. If, after a period of time, no reply appears in your single thread, the better approach is to reply to your own post. You might even use that opportunity to add some details that would improve the prospects of a useful reply. However, 0.4 hours is too short a time to do either.