Sudden slow download speed on MBP

[DKTR]

So I was downloading a few TV shows while at uni this afternoon. All went well and normal but I had to pause the downloads and get home to run some errands. I got home, plug in the Ethernet cable and continue with my downloads. However, it came to my attention that the download speed only max out around 30kb/s (wireless and Ethernet) while its average around 600kb/s - 800kb/s (wireless and Ethernet) everyday at home and ~1mb/s at uni (wireless). While I can surf the web, play YouTube video at normal speed (no waiting to buffer), only the download speed is affecting. I tried different files, different hosts, different browsers, even different internet connections; the problem still remains. I also cleared cache, history, cookie, repair permissions and finally reinstall Mac OS X but failed to do any good. So now I'm seeking help from Mac users. Any suggestion to fix my frustrating problem is much appreciated.

Mine is the base model MacBook Pro 15" i5 2010; was running 10.6.7, now running 10.6.3.

Thanks heaps.

PS: This is my Wireless ADSL Modem status.
DownStream Connection Speed 6496 kbps
UpStream Connection Speed 384 kbps