How to Fix DPC Latency Audio Crackling on Your Computer

Published 2026-10-16 · LuxuriousComputers Repair

Your computer's audio crackles, pops, stutters, or has brief dropouts during music playback, video calls, or gaming. The sound breaks up for a fraction of a second, then returns to normal, then breaks again. This is not a speaker or headphone problem — it happens on any audio output device. The cause is DPC latency: a driver or system process is hogging the processor for too long, starving the audio system of the regular, timely attention it needs to produce smooth sound.

What DPC latency is

DPC stands for Deferred Procedure Call. Windows uses DPCs to let hardware drivers process their work. Every driver gets brief time slices to handle its tasks. Audio playback requires the sound driver to receive and process audio data at precise intervals — typically every 10 milliseconds or less. When another driver takes too long with its DPC (more than 1 to 2 milliseconds), the audio driver misses its window and the result is an audible glitch: a crackle, pop, or brief silence.

DPC latency issues are tricky because the audio hardware and drivers are usually not the problem. The problem is some other driver (network, GPU, USB, storage) disrupting the system's ability to service audio on time.

Measure DPC latency

Before fixing anything, confirm that DPC latency is actually the problem:

LatencyMon

1. Download LatencyMon (free from Resplendence Software)
2. Run it and click the Play button to start monitoring
3. Use the computer normally for a few minutes, doing whatever triggers the audio crackling
4. LatencyMon shows which drivers are causing the highest latency. The Drivers tab lists every driver sorted by highest execution time. Drivers highlighted in red or yellow are taking too long
5. If the highest reported DPC latency is consistently above 1000 microseconds (1 millisecond), DPC latency is likely causing your audio issues. Above 2000 microseconds, crackling is almost certain

Common high-latency drivers

• ndis.sys, tcpip.sys, or a network adapter driver: Network drivers are the most common cause. Wi-Fi drivers are especially problematic
• nvlddmkm.sys (NVIDIA) or atikmpag.sys (AMD): Graphics drivers, especially during GPU state changes (entering/exiting full-screen, switching displays)
• storport.sys, stornvme.sys: Storage drivers, often related to power management
• USBPORT.sys or a USB controller driver: USB devices or controllers with driver issues
• Wdf01000.sys: Windows Driver Framework — indicates a driver built on WDF is misbehaving, check the stack trace for the actual culprit

Fix network driver latency

Network drivers cause DPC latency more than any other category:

Disable network power management

1. Open Device Manager, expand Network Adapters
2. Right-click your network adapter (both Wi-Fi and Ethernet), select Properties
3. Power Management tab: uncheck Allow the computer to turn off this device to save power
4. Advanced tab: look for settings like Energy Efficient Ethernet, Green Ethernet, Power Saving Mode, Wake on Magic Packet, and Wake on Pattern Match. Disable all of these. Each one adds latency when the adapter transitions between power states

Update or replace network drivers

• Download the latest driver from the adapter manufacturer (Intel, Realtek, Qualcomm/Atheros, Killer) rather than using Windows Update drivers. Manufacturer drivers are often more optimized for latency
• Intel Wi-Fi adapters: download Intel Driver and Support Assistant. Intel frequently releases driver updates that fix DPC latency issues
• If a Wi-Fi driver is consistently causing high latency and updates do not help, using a wired Ethernet connection eliminates the problem entirely. Wi-Fi drivers are inherently more complex and latency-prone than Ethernet drivers

Fix GPU driver latency

• Update the graphics driver: Download directly from NVIDIA GeForce Experience, AMD Radeon Software, or Intel. Do a clean installation (NVIDIA: check Custom Installation, Clean Install. AMD: check Factory Reset)
• Disable GPU power management features: In NVIDIA Control Panel, set Power Management Mode to Prefer Maximum Performance. In AMD Radeon Settings, disable power-saving features. These prevent the GPU from constantly switching power states, which causes DPC spikes
• Disable hardware acceleration in browsers: Chrome, Firefox, and Edge use GPU hardware acceleration by default. When the GPU driver has latency issues, browser hardware acceleration triggers DPC spikes during video playback or page scrolling. Disable it in the browser's settings (Settings, System, Use hardware acceleration)

Fix USB latency

• Disconnect USB devices one at a time while monitoring with LatencyMon. If removing a specific device drops the latency, that device's driver is the cause
• USB 3.0 controllers are frequent latency offenders. In Device Manager, expand Universal Serial Bus Controllers, right-click each USB controller, Properties, Power Management — disable power saving
• If a USB audio interface is involved, make sure it is using its manufacturer's ASIO driver, not the Windows generic USB audio driver

System-wide power management

Windows power management causes many DPC latency issues because multiple drivers transition between power states:

1. Open Control Panel, Power Options
2. Select the High Performance power plan (you may need to click Show Additional Plans to see it). If it does not exist, create one
3. Click Change Plan Settings, Change Advanced Power Settings
4. Set Processor Power Management, Minimum Processor State to 100 percent. This prevents the CPU from downclocking, which eliminates latency spikes from frequency transitions
5. Set PCI Express, Link State Power Management to Off. This prevents PCIe devices (GPU, NVMe SSD, network cards) from entering low-power states
6. Set USB Settings, USB Selective Suspend to Disabled

Disable problem services

• Windows Search indexing: The search indexer can cause storage DPC spikes while indexing files. If LatencyMon shows storage driver latency, try pausing or disabling Windows Search temporarily (Services, Windows Search, set to Disabled) and test
• Superfetch/SysMain: This prefetching service causes disk activity spikes. Services, SysMain, set to Disabled if storage latency is high
• Windows Defender real-time scanning: Defender scanning files during audio playback can cause brief DPC spikes. Add your audio project folders and DAW application to Defender's exclusion list (Settings, Windows Security, Virus Protection, Manage Settings, Add Exclusion)

BIOS settings

• C-States: CPU C-States are power-saving states that reduce power when the CPU is idle. Transitioning between C-States takes time and causes latency spikes. Enter BIOS and disable C-States (often labeled C1E, C3, C6, or Package C-State). This increases power consumption slightly but eliminates CPU power transition latency
• SpeedStep or Cool'n'Quiet: Intel SpeedStep (EIST) and AMD Cool'n'Quiet dynamically adjust CPU frequency. Disabling them locks the CPU at full speed, preventing frequency transition latency
• HPET: The High Precision Event Timer can cause latency on some systems. Try disabling it in BIOS and test. On some configurations, disabling HPET improves DPC latency; on others, it makes it worse. Test both ways

Audio driver and buffer settings

While the audio driver usually is not the root cause, optimizing it helps tolerate small DPC spikes:

• Increase audio buffer size: In your audio application or sound card settings, increase the buffer size from 128 to 256 or 512 samples. Larger buffers tolerate longer DPC interruptions without audible glitches. The tradeoff is slightly higher audio latency (delay between input and output)
• ASIO drivers: If you use professional audio software, ASIO drivers bypass much of the Windows audio stack and are more resilient to DPC issues. Use ASIO4ALL (free) if your audio device does not have a native ASIO driver
• Exclusive mode: In Windows Sound Settings, device Properties, Advanced, enable Allow applications to take exclusive control. This gives audio applications direct access to the audio device, reducing the overhead of the Windows audio mixer

Clean boot test

If you cannot identify the specific driver causing high DPC latency:

1. Press Windows+R, type msconfig, Enter
2. Services tab: Hide All Microsoft Services, Disable All
3. Startup tab: Open Task Manager, disable all startup items
4. Restart and run LatencyMon. If DPC latency is now normal, a third-party service or startup program was the cause. Re-enable services in groups to find the culprit

DPC latency diagnosis in Columbus or Delaware

If your computer has persistent audio crackling and popping caused by DPC latency and the troubleshooting above did not resolve it, LuxuriousComputers can run detailed latency analysis, identify the specific driver or hardware component causing the problem, and apply targeted fixes to eliminate the audio glitches.