Manually flash the LinkStation's firmware
From NAS-Central Buffalo - The Linkstation Wiki
Different Architectures | This method can be applied to all versions of the LinkStation. Simply substitute the appropriate flash bank for /dev/fl1.
1. Do not manually flash your firmware unless you are absolutely sure about what you're doing! You should read the flash ROM analysis at LinkStation Information before proceeding.
2. You will need the firmimg.bin of your desired firmware. Copy firmimg.bin to your LinkStation.
3. Open up an SSH or telnet session to the LinkStation. Copy firmimg.bin to the /dev/fl1 flash bank:
cat firmimg.bin > /dev/fl1
4. The LinkStation LEDs will begin flashing red; this is normal! The flash process may take several minutes. Absolutely do not turn off the LinkStation, terminate the SSH/telnet session, or in any other way interrupt the flash process. The LEDs will return to normal when the flash process is complete.