first thoughts

Try and get the SB Live on its own IRQ. If you don't need the SB16 emulation (if you don't know, you probably don't need it), disable it. To do this, open your autoexec.bat in Notepad. 3 lines for SB16 emulation start like this:

SET BLASTER=
SET CTSYN=
C:\PROGRA~1\CREATIVE\...

Type "rem" (without the quotes) in front of each line.

Do you have a printer, USB device, or serial device? I'm guessing your modem is PCI since it shows up with its own IRQ. Go into the BIOS and disable any ports you don't need.

If your SB Live still shares an IRQ, try the PCI shuffle. Your Promise card has its own IRQ (for the most part), so I'd try switching that and the SB Live first.