I have a task that it blocks waiting for an item to be posted on a queue. The item is posted from an ISR. The first item posted on the queue unblocks the task successfully. The second item also unblock the task but when the task returns to the blocking receive the system get stuck. I don´t see anything strange in the memory, the stacks of the tasks are ok. I tried everything, I removed all the code from the task, I only leaved a led toggle. I need suggestions of what could be the problem.