If someone could answer me in Italian it's better, but don't worry...!

I could listen low sounds from any applications: if I use XMMS playing an mp3, the sound is good but there aren't any low frequences.
I have Hercules Fortissimo 2 soundcard (chipset 4624) and 2.1 speakers; the board has many outputs: the only that works is at the behind speakers (it's a 4.1 soundcard), but in Windows98 everything is ok.

I have tried to use OSS, Alsa and many more, but with no results

I can give you other details, if you want...

I'm sorry for my English. I hope in an answer