BSOD - Error log enclosed, please help

I've got a Dell D630 with a blue screen issue, could somebody please take a look at the crash dump file below and see if they can make anything of it.

 

From what I can see there has been an IRQ conflict with the sound card. Can anybody go further than this or recomend some resolutions. Normally I'd just format the machine down and reimage it to get it back in service as quickly as possible (When a Pc starts BSODing, its often not economical to fix), but this particular machine has a custom setup with some particularly heavy hitting installs which I can't just reinstall from an image.

 

Any suggestions would be appreicaiated.

 

DRIVER_IRQL_NOT_LESS_OR_EQUAL (d1)
An attempt was made to access a pageable (or completely invalid) address at an
interrupt request level (IRQL) that is too high.  This is usually
caused by drivers using improper addresses.
If kernel debugger is available get stack backtrace.
Arguments:
Arg1: 00000000, memory referenced
Arg2: 00000002, IRQL
Arg3: 00000001, value 0 = read operation, 1 = write operation
Arg4: b84e15b9, address which referenced memory

Debugging Details:
------------------

 

WRITE_ADDRESS:  00000000

CURRENT_IRQL:  2

FAULTING_IP:
sthda+75b9
b84e15b9 8908            mov     dword ptr [eax],ecx

DEFAULT_BUCKET_ID:  DRIVER_FAULT

BUGCHECK_STR:  0xD1

PROCESS_NAME:  Idle

LAST_CONTROL_TRANSFER:  from 8050193b to b84e15b9

STACK_TEXT: 
WARNING: Stack unwind information not available. Following frames may be wrong.
805503fc 8050193b 8055b0a0 ffdff9c0 ffdff000 sthda+0x75b9
80550428 805451ff 8055b4a0 00000000 0000f781 nt!MiGatherMappedPages+0x241
ffdff980 00000000 bacd4000 00011251 00000000 nt!WmiTraceMessageVa+0x166

STACK_COMMAND:  kb

FOLLOWUP_IP:
sthda+75b9
b84e15b9 8908            mov     dword ptr [eax],ecx

SYMBOL_STACK_INDEX:  0

SYMBOL_NAME:  sthda+75b9

FOLLOWUP_NAME:  MachineOwner

MODULE_NAME: sthda

IMAGE_NAME:  sthda.sys

DEBUG_FLR_IMAGE_TIMESTAMP:  46434181

FAILURE_BUCKET_ID:  0xD1_W_sthda+75b9

BUCKET_ID:  0xD1_W_sthda+75b9

Followup: MachineOwner
---------

0: kd> lmvm sthda
start    end        module name
b84da000 b85f7940   sthda    T (no symbols)          
    Loaded symbol image file: sthda.sys
    Image path: sthda.sys
    Image name: sthda.sys
    Timestamp:        Thu May 10 17:00:01 2007 (46434181)
    CheckSum:         00137C8C
    ImageSize:        0011D940
    Translations:     0000.04b0 0000.04e0 0409.04b0 0409.04e0