This is the screenshot from the main page LatencyMon:
and the results:
CONCLUSION
Your system appears to be having trouble handling real-time audio and other tasks. You are likely to experience buffer underruns appearing as drop outs, clicks or pops. One problem may be related to power management, disable CPU throttling settings in Control Panel and BIOS setup. Check for BIOS updates.
LatencyMon has been analyzing your system for 4:30:45 (h:mm:ss) on all processors in the system.
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SYSTEM INFORMATION
Computer name: VM-PC
OS version: Windows 7 Service Pack 1, 6.1, build: 7601 (x64)
CPU: GenuineIntel Intel(R) Core™ i7 CPU 920 @ 2.67GHz
Logical processors: 4
Processor groups: 1
RAM: 8182 MB total
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CPU SPEED
Reported CPU speed: 2672.0 MHz
Measured CPU speed: 2989.0 MHz (approx.)
Note: reported execution times may be calculated based on a fixed reported CPU speed. Disable variable speed settings like Intel Speed Step and AMD Cool N Quiet in the BIOS setup for more accurate results.
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MEASURED KERNEL TIMER LATENCIES
Highest measured kernel timer latency (µs): 2242.403299
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MEASURED SMIs AND CPU STALLS
Highest measured SMI, IPI or CPU stall (µs) 0.766241
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REPORTED DPCs
Highest DPC routine execution time (µs): 286.393713
Driver with highest DPC routine execution time: nvlddmkm.sys - NVIDIA Windows Kernel Mode Driver, Version 295.73 , NVIDIA Corporation
Highest reported total DPC routine time (%): 1.777342
Driver with highest DPC total execution time: ohci1394.sys - 1394 OpenHCI Port Driver, Microsoft Corporation
Total time spent in DPCs (%) 2.614944
DPC count (execution time <250 µs): 212565903
DPC count (execution time 250-500 µs): 0
DPC count (execution time 500-999 µs): 1
DPC count (execution time 1000-1999 µs): 0
DPC count (execution time 2000-3999 µs): 0
DPC count (execution time >=4000 µs): 0
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REPORTED ISRs
Highest ISR routine execution time (µs): 190.152695
Driver with highest ISR routine execution time: ataport.SYS - ATAPI Driver Extension, Microsoft Corporation
Highest reported total ISR routine time (%): 0.518007
Driver with highest ISR total time: ohci1394.sys - 1394 OpenHCI Port Driver, Microsoft Corporation
Total time spent in ISRs (%) 0.708194
ISR count (execution time <250 µs): 106636514
ISR count (execution time 250-500 µs): 0
ISR count (execution time 500-999 µs): 0
ISR count (execution time 1000-1999 µs): 0
ISR count (execution time 2000-3999 µs): 0
ISR count (execution time >=4000 µs): 0
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REPORTED HARD PAGEFAULTS
Process with highest pagefault count: none
Total number of hard pagefaults 5672
Hard pagefault count of hardest hit process: 2230
Highest hard pagefault resolution time (µs): 189424.618263
Total time spent in hard pagefaults (%): 0.032147
Number of processes hit: 0
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PER CPU DATA
CPU 0 Interrupt cycle time (s): 471.445887
CPU 0 ISR highest execution time (µs): 13.125749
CPU 0 ISR total execution time (s): 19.223901
CPU 0 ISR count: 19895642
CPU 0 DPC highest execution time (µs): 165.077844
CPU 0 DPC total execution time (s): 291.939502
CPU 0 DPC count: 124210992
CPU 1 Interrupt cycle time (s): 367.558870
CPU 1 ISR highest execution time (µs): 190.152695
CPU 1 ISR total execution time (s): 104.112283
CPU 1 ISR count: 9046955
CPU 1 DPC highest execution time (µs): 286.393713
CPU 1 DPC total execution time (s): 226.823998
CPU 1 DPC count: 8492529
CPU 2 Interrupt cycle time (s): 1426.126810
CPU 2 ISR highest execution time (µs): 17.947605
CPU 2 ISR total execution time (s): 336.765682
CPU 2 ISR count: 77686924
CPU 2 DPC highest execution time (µs): 198.534431
CPU 2 DPC total execution time (s): 1159.103831
CPU 2 DPC count: 77807482
CPU 3 Interrupt cycle time (s): 58.773454
CPU 3 ISR highest execution time (µs): 23.016467
CPU 3 ISR total execution time (s): 0.096304
CPU 3 ISR count: 6993
CPU 3 DPC highest execution time (µs): 64.491018
CPU 3 DPC total execution time (s): 21.373416
CPU 3 DPC count: 2054901