I have two computers here, both have Avast installed. On the newer machine, which is a win7 x64 i7 with 16gb of RAM, when the web shield is turned on, my speed is cut down to about 4kbps. While this is happening, the other machine is still at 30-40kbps. If I turn the web shield off, my speed immediately goes back to 30-40kbps. It still happens if I unselect streaming in the advanced options.
The machine that is unaffected is a win7 x64 Core 2 Duo with 4gb of RAM. This leads me to believe this bug could possibly have to do with Win 7 x64 addressing more than 4gb of RAM.
I just wanted to report it here, and see if anyone else is encountering the same problem.