BSOD random times, IRQL_GT_ZERO_AT_SYSTEM_SERVICE 0x0000004a

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Code:

Microsoft (R) Windows Debugger Version 6.2.9200.20512 AMD64
Copyright (c) Microsoft Corporation. All rights reserved.

Loading Dump File [C:\Users\USER\Downloads\SF_15-12-2013\SF_15-12-2013\121513-16582-01.dmp]
Mini Kernel Dump File: Only registers and stack trace are available
Symbol search path is: SRV*c:\symbols*http://msdl.microsoft.com/download/symbols
Executable search path is: 
Windows 7 Kernel Version 7601 (Service Pack 1) MP (2 procs) Free x64
Product: WinNt, suite: TerminalServer SingleUserTS
Built by: 7601.18247.amd64fre.win7sp1_gdr.130828-1532
Machine Name:
Kernel base = 0xfffff800`02e67000 PsLoadedModuleList = 0xfffff800`030aa6d0
Debug session time: Mon Dec 16 00:58:05.143 2013 (UTC + 6:00)
System Uptime: 0 days 0:05:30.392
Loading Kernel Symbols
...............................................................
................................................................
.........................................
Loading User Symbols
Loading unloaded module list
....
*******************************************************************************
*                                                                             *
*                        Bugcheck Analysis                                    *
*                                                                             *
*******************************************************************************
Use !analyze -v to get detailed debugging information.
BugCheck 4A, {7714132a, 2, 0, fffff88009c2cb60}
Probably caused by : ntkrnlmp.exe ( nt!KiSystemServiceExit+245 )
Followup: MachineOwner
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1: kd> !analyze -v
*******************************************************************************
*                                                                             *
*                        Bugcheck Analysis                                    *
*                                                                             *
*******************************************************************************
IRQL_GT_ZERO_AT_SYSTEM_SERVICE (4a)
Returning to usermode from a system call at an IRQL > PASSIVE_LEVEL.
Arguments:
Arg1: 000000007714132a, Address of system function (system call routine)
Arg2: 0000000000000002, Current IRQL
Arg3: 0000000000000000, 0
Arg4: fffff88009c2cb60, 0
Debugging Details:
------------------

PROCESS_NAME:  vsserv.exe
BUGCHECK_STR:  RAISED_IRQL_FAULT
FAULTING_IP: 
+0
00000000`7714132a ??              ???
CUSTOMER_CRASH_COUNT:  1
DEFAULT_BUCKET_ID:  WIN7_DRIVER_FAULT
CURRENT_IRQL:  2
LAST_CONTROL_TRANSFER:  from fffff80002edc169 to fffff80002edcbc0
STACK_TEXT:  
fffff880`09c2c928 fffff800`02edc169 : 00000000`0000004a 00000000`7714132a 00000000`00000002 00000000`00000000 : nt!KeBugCheckEx
fffff880`09c2c930 fffff800`02edc0a0 : 00000000`00000a74 fffff880`09c2cb60 00000000`00000000 fffff800`031c6383 : nt!KiBugCheckDispatch+0x69
fffff880`09c2ca70 00000000`7714132a : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : nt!KiSystemServiceExit+0x245
00000000`21abfcc8 00000000`00000000 : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : 0x7714132a

STACK_COMMAND:  kb
FOLLOWUP_IP: 
nt!KiSystemServiceExit+245
fffff800`02edc0a0 4883ec50        sub     rsp,50h
SYMBOL_STACK_INDEX:  2
SYMBOL_NAME:  nt!KiSystemServiceExit+245
FOLLOWUP_NAME:  MachineOwner
MODULE_NAME: nt
IMAGE_NAME:  ntkrnlmp.exe
DEBUG_FLR_IMAGE_TIMESTAMP:  521ea035
FAILURE_BUCKET_ID:  X64_RAISED_IRQL_FAULT_vsserv.exe_nt!KiSystemServiceExit+245
BUCKET_ID:  X64_RAISED_IRQL_FAULT_vsserv.exe_nt!KiSystemServiceExit+245
Followup: MachineOwner
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