Very slow connection with USB modem

Hi,

I just bought a new USB modem (Creative Modem Blaster USB, 56K) to replace my old serial port modem (external, 56K). When I set it up and tested it, I found out that this new modem is a lot slower (about 3 times slower) than the old one. Withmy old modem, I could download files at at least 3.x K/s, but with the new one the fastest speed only reached 1.2 K/s. So my question is, are USB modems actually SLOWER than serial modems, or is my case a weird exception? Is there any way to improvethe performance of a USB modem?

Any thoughts or suggestions will be appreciated. Thanks

Rgds,
Kom