Sometimes you may meet this problem when you adjust the clock time on the device. You can correct it by the firmware update: 1. Download the firmware to your PC via the link Firmware download 2. Unzip the downloaded file, you will get a file named philips.bin Attention: Do not rename the file to avoid firmware upgrade failure. 3. Copy the file into a SD card. Make sure the SD card is compatible with the device. 4. Switch on the device 5. Insert the SD card. The firmware upgrade will auto start.