Help! Medit 5.5 on Windows XP Pro

[vortec]

I'm not a techie! Please help!

I recently upgraded my computer and OS to Windows XP Professional and installed a fresh copy of Medit 5.5. But when I ran the Setup Test, the Krystal board passed all the tests EXCEPT the Krystal Interrupt Test, which it failed.

Another strange symptom worth mentioning is that when I was installing the Medit program, the following error message appeared just before the installation finished:
MSND32 DLL Error
MTUMSND.SYS device drive not loaded or not functioning properly. Please make sure MTUMSND device has been started

I have tried installing the Krystal card in various PCI slots. Made sure it was properly seated, etc. But to no avail. The Krystal card does show up under the Windows Device Manager as a "Multimedia Controller" with a yellow bold question mark next to it (this, I assume, is normal since it was this way under Medit 5.4 running on my old Win 98 machine).

Other relevant information. In the Windows system information hardware resource section, it shows IRQ 17 assigned to the device "Mtumsnd." But it also shows a device called "Multimedia Controller" (presumably the Krystal card, though I'm not sure) with IRQ 11 assigned to it.

The installation manual for Medit 5.5 only shows instructions for Windows 98. So I'm not sure if I've configured the settings properly to work in Windows XP, though I have a feeling this is not the cause of the problem I'm experiencing.

My computer's specs:
MS Windows XP Professional
Intel Pentium IV 2.4 GHz chip on Intel D845GBV2 motherboard.
The only additional cards installed are Adaptec AIC-786X PCI SCSI and Realtek RTL8139 LAN card. Video and sound came on board the Intel motherboard.

Previously had no problem running Medit 5.4 on Windows 98, on Pentium III machine.

Again, HELP! And thanks.