If your HD300A doesn't boot or behaves strangely, please try Safe Mode (Emergency Recovery) Firmware Upgrade:
* Turn off HD300A, and remove all HDDs, USB devices and network
* Unrar the downloaded firmware into the root of USB disk, rename the .img file to install.img, and connect the USB disk to HD300A
* Press and hold the Restore button in the hole besides the external SATA port, turn on HD300A(still hold the Restore button down) and wait for 30~60 seconds till the firmware upgrade screen shows up