I am using iMX357 processor along with MC13892AJVL, 256Mbyte DDR2 and 256MByte NAND Flash. The board was working very good for 6months, but after that some irregular behavior started: 1. In some cases the processor is not booting when Power supply turned ON. In close observation we found that this is happening when the power OFF to ON time is very less(approximately 2 seconds or less). 2. In some cases the processor not booting immediately but after a few seconds only( approximately 1 or 2 seconds) 3. Manual reset connected to RESET_IN_B pin was working perfectly earlier but it stopped working now. All these issues started after a time of 6months. During this time the board was working perfectly and we were developing some application software. Please let me know if anybody have experience in the same or any idea about these issues?