can't open /dev/dsp!

Hello, Fed up of SuSE 7.3. Everything went fine with SuSE 7.2, now with SuSE 7.3 I can't use my usb scanner HP6200c (I could with SuSE 7.2) and if I want to listen to a mp3 file I have the answer "can't open /dev/dsp!". The sound card is normally installed with alsaconf. Does anyone know how to open /dev/dsp? Thanks -- Alain Barthélemy