p2p sharing uses up a lot of bandwidth. Some ISP's shape p2p sharing so they can make more money selling it to business. Whilst some ISP's offer high speeds or so called unlimited bandwidth, they only expect surfers to use this, not heavy bandwidth users such as gamers & p2p file sharers. Thus some ISP's choose to shape it for such programs using special tools. It does look like this is your scenario if it is happening with all types of files. Interesting to see if the same thing happens if you use a different gnutella program such as Phex: http://www.phex.org/wiki/index.php/Get_Phex