I have done that a few times. I have forcably uploaded the firmware. I have turned it off and on again and off and on again. Last night I had a utorrent running on a laptop with the same ports forwarded and was getting 950kbs average for the same torrents the Linkstation is trying to download.
The Linkstation was getting 10kbps when I moved the port forwarding back. From reading other forums this fault is common but people are quick to blame the ISP, it's just not the case here.
The network is fine, the ISP is fine, the NAS is dire.
This is a massive problem with the unit and all testing narrows the problem down to the unit and its firmware. When is the next firmware due out?
It's a shame I can't bill Buffalo for hours spent trying to workaround an inherent fault with the unit, I could quit my day job.