Thanks for your answer johnl12.
I tried your new commands but the sound is still crackling in space.
I could not find the files sndscape.ini and ctsyn.ini.
The command "J200" in autoexec.bat (set blaster)is always deleted ,i think, by windows. But it does not matter because the sound is still crackling although i play direct from dos without starting windows before.
My new autoexec.bat :
SET PATH=C:\WINDOWS;C:\WINDOWS\COMMAND
SET TEMP=C:\TEMP
PROMPT $p$g
SET BLASTER=A220 I7 D1 H7 P330 T6 J200
SET SBPCI=C:\PROGRA~1\CREATIVE\AUDIO\DOSDRV
c:\progra~1\creative\audio\dosdrv\sbinit.com
c:\mouse\mouse.exe
My new config.sys :
DEVICE=C:\WINDOWS\HIMEM.SYS
DEVICE=C:\windows\EMM386.EXE 16384 RAM D=64 FRAME=E000 /I=B000-B7FF
DEVICE=C:\WINDOWS\SMARTDRV.EXE 1024
dos=high
dos=umb
stacks=18,256
Buffershigh=30
Fileshigh=30
Lastdrive=G