“Blessed are those who do not encounter a blue screen of death error on their Windows 10 computers, for they shall be spared the agony of endless hours of searching for solutions” should be a beatitude when the Windows Bible is eventually compiled.

Seriously, blue screens of death errors on Windows are a user’s absolute worst nightmare. The mere thought of being stuck in no man’s land because of a sudden system crash is enough to send shivers down the spine of many people, especially hardcore PC users and gamers. To make matters worse, some of the error messages are not much help towards solving the issue.

CMUSBDAC.sys SYSTEM_THREAD_EXCEPTION_NOT_HANDLED is a member of the annoying BSOD family of errors that has been affecting users for a while now. Though it has been around for a long time, instances of this error spiked after Windows 10 users installed the Cumulative Update KB4016635. This guide explains what this error is and how to combat it with effective solutions that help you regain complete control of your system.

What is the CMUSBDAC.SYS Blue Screen Error?

Before we delve into how to get rid of the CMUSBDAC.sys BSOD, it is pertinent to examine the nature of the error. CMUSBDAC stands for C-Media USB DAC Device Driver. Basically, it is the driver that handles communications between the OS and connected USB audio devices. Without this driver, any plugged peripheral like a microphone, for example, won’t work.

Any slight problem with this driver can result in a blue screen of death with an accompanying SYSTEM_THREAD_EXCEPTION_NOT_HANDLED stop error message. It might be that the driver is outdated or corrupt. Perhaps, it has been infected by malware or its functions changed by harmful code.

This isn’t to say that it is always the cause of the error. Besides malware, bad RAM sectors and damaged storage drives can trigger the error as well.

The CMUSBDAC.sys error commonly occurs after updating the firmware, meaning faulty update components might be at play here. Gamers have also reported sudden crashes in the middle of certain demanding games. Unless it is solved, it will continue to happen at random multiple times a day. This, of course, isn’t a state of affairs users can stomach. Hence, this guide is compiled to help you solve the problem and stop the frequent restarts.

How to Fix the CMUSBDAC.sys Blue Screen on Windows 10

Since the outbreak of complaints over the SYSTEM_THREAD_EXCEPTION_NOT_HANDLED (CMUSBDAC.SYS) error on Windows, there has been hope that Microsoft is working on an official fix that would solve the problem once and for all. While you wait along with the rest of the Windows community, there are things you can try in the meantime. So, we have rounded up the best solutions for the error as discovered through research and sampling user feedback.

  • Perform an Antivirus Scan

As observed, errors of this nature can actually be due to malware infection rather than any intrinsic problems with the Windows input/output driver that enables sound from the microphone. Instead of restarting your computer, what you should do, first of all, is to scan your computer for possible malware. Who knows, harmful code disguised as a genuine system file might be hiding among your system folders and wreaking untold havoc. Even if you are skeptical about this being the cause, it is in your best interest to verify that this is indeed not the case.

There are a lot of security software you can use. Windows Defender Firewall is no slouch either, especially on Windows 10. You can also use Auslogics Anti-Malware to perform a deep system scan to ferret out malware, some of which might be hiding in the unlikeliest of places.

  • Update the C-Media USB Device Audio Class Driver with Device Manager

Because the C-Media USB Device Audio Class Driver is crucial to the proper functioning of the USB microphone and other I/O sound devices on the computer or connected to it, any problems at all with the file generally have wide-ranging repercussions. If you find that you’re getting frequent blue screens of death with CMUSBDAC.sys error messages, the solution likely lies with making sure that the driver isn’t corrupt or damaged.

The moment you regain access to your OS after a BSOD, check that the C-Media USB Device Audio Class Driver is working normally. Go to Device Manager and look for the driver under Sound, video and game controllers or Audio inputs and outputs. When you find it, either double-click it or right-click and select Properties. Review what it says in the Device status box in the General tab. If it says anything apart from “Your device is working properly”, there’s likely something wrong with it.

Even if the status information assures you that the device is in fact working properly, the SYSTEM_THREAD_EXCEPTION_NOT_HANDLED (CMUSBDAC.sys) error might beg to differ. To eliminate the driver from the discussion as a possible culprit, you must first of all update it and see if it solves your issue. If it doesn’t, you have the option to reinstall it and see if that works instead.

The best way to update the C-Media USB Device Audio Class Driver is through Device Manager. Here’s how:

  • Press the Windows key + X to bring up the Windows Tools menu. Select Device Manager from the menu list.
  • Expand the Sound, video and game controllers node to reveal the driver. If it isn’t there, check under the Audio Inputs and outputs node.
  • Right-click the driver and click Update Driver Software.
  • In the next window, select the “Search automatically for updated driver software” option and Windows will find, download and install the latest driver on your system.
  • Reboot your PC.

Sometimes, Windows tells you that the driver is up to date but your visit to the resource section of the manufacturer’s website clearly showed that there is a later version available. In that case, download the compatible driver for your device and place it somewhere convenient. Then return to Device Manager and when you click Update Driver Software, select the “Browse my computer for driver software”x option in the next window. Find your downloaded and unzipped file and install it.

If the problem persists after a reboot, completely uninstalling the driver and installing it afresh might work. The process is similar to the one above:

  • Press the Windows key + X to bring up the Windows Tools menu. Select Device Manager from the menu list.
  • Expand the Sound, video and game controllers node to reveal the driver. If it isn’t there, check under the Audio Inputs and outputs node.
  • Right-click the driver and click Uninstall.
  • Restart your computer.
  • Return to Device Manager.
  • Click the Action tab at the top and select Scan for hardware changes.
  • Once the C-Media USB Device Audio Class Driver shows up in the results, click Install driver and wait while Windows installs the latest version of the driver it can find. If that doesn’t work, install the driver manually as explained above.

With a fresh C-Media USB Device Audio Class Driver on your Windows 10 PC, the frequent blue screen errors should now be a thing of the past. If they remain very much a thing of the present after trying this fix, move over to the next solution.

  • Return to an Earlier Restore Point

You have probably been using your USB microphone for a long time without any issues until suddenly the CMUSBDAC.sys error reared its ugly head. It then means that something must have happened to trigger the error, even if you aren’t exactly sure what that is. Maybe a recent update messed up something. Perhaps the driver in question became corrupted. Maybe it’s something else.

Whatever it is, you can solve it by simply going back in time to an earlier point before the error started happening. This is, of course, achievable through System Restore in Windows. Assuming that you’ve enabled System Restore and already created multiple restore points for just such an eventuality, now is the time to use it for what it was created for.

For the best results, we recommend you perform your system restore through Safe Mode. This will allow the operation to proceed without undue interference from installed drivers and other components. Here’s how to do it in Windows 10:

  • Launch the Settings application. Click the Windows key to bring up the Start menu and select Settings.
  • Go to Update & Security > Recovery > Open Recovery Settings.
  • Click Restart now under the Advanced startup option. Your computer will restart into Windows Recovery Environment.
  • On the Choose an optionscreen, click Troubleshoot.
  • Click Advanced options.
  • Click Startup Settings.
  • Click Restart.
  • The computer boots into the Startup Settings options screen. Press 4 on your keyboard to boot into Safe Mode.

At this point, it is a good idea to turn off your antivirus (if Safe Mode hasn’t already done so)

  • Launch Control Panel from the Windows Tools menu.
  • Change the View by mode to icon view.
  • Click Recovery.
  • Click Open System Restore.
  • Click Nextin the next window.
  • The “Restore your computer to the state it was in before the selected event” window is displayed. You will see a list of your automatically and manually created restore points here.
  • Select a restore point created before the CMUSBDAC.sys error started happening.
  • Click Next.
  • Click Finish.

Your machine will reboot once Windows has finished restoring to an earlier point. Now, check that you’re not experiencing any more blue screen of death CMUSBDAC.sys issues.

  • Fix the Problematic Driver

Sometimes it isn’t the C-Media USB Device Audio Class Driver that is causing the issue but another hardware support software. Perhaps, the specific culprit is hard to identify. However, once you’ve discovered it, you can use the method shown in the second solution to update or reinstall that driver via Device Manager.

You can check the minidump file created by a BSOD event to isolate the problematic drivers. Though this isn’t always the case, it’s better to check:

  • Click the Windows Explorer icon on your taskbar.
  • Find This PC in the left pane, right-click it and click Properties.
  • Click the Advanced system settings link in the left pane.
  • Click the Settings button under the Startup and Recovery section in the System Properties window under the Advanced tab.
  • Tick the “Write an event to the system log” and “Automatically restart” checkboxes under the System failure section.
  • Open the “Write debugging information” dropdown menu and select “Small memory dump (256kb)”.
  • Click OK when you’re done.

Now that you’ve enabled minidump, the next time your PC crashes due to a CMUSBDAC.sys issue or any other stop error, Windows creates a minidump which you can analyze to identify the problematic driver or program.

Even though minidump files aren’t exactly easy to decipher, you can analyze them with a tool like Windows Debugger (WinDbg).

  • Download and install the Windows Debugging Tool and the correct symbol package for Windows 10
  • Type “WinDbg” (no quotes) in the Start window and click to launch when it shows up in the results.
  • In the File tab, click Symbol File Path and navigate to the location of the downloaded symbol package.
  • Click Open Crash Dump in the File tab and select the latest minidump file from C:\Windows\Minidump.
  • Type “analyze -v” (without quotes) in the input box and press Enter to begin analyzing the minidump.
  • Check under MODULE_NAME” and “IMAGE_NAME” headings to find the culprit driver causing the BSOD issue.

As you can see, this method is a bit on the technical side. It is easy to get lost unless you’re well versed in the intricacies of using developer tools for Windows.

If you don’t have the time to labor over finding whichever driver is responsible for your CMUSBDAC.sys error, you can just update all your drivers in one fell swoop. This not only brings your hardware drivers up to date, but also eliminates the problematic driver by replacing it with a new/uncorrupted version. As a matter of fact, the most effective way to get rid of driver-related errors is by updating all your drivers.

You may use the method described in the section on the C-Media USB Device Audio Class Driver Device Driver to update or install the latest versions of all the drivers on your computer, or at least those you believe require updating.

However, chances are Windows won’t find some of these drivers through the “Update driver” feature in Device Manager. Therefore, to get rid of blue screen of death errors on your computer if you don’t know which driver in particular is causing it, you’re left with two options: you can update your drivers manually or do so with the aid of an automatic driver updating software.

  • Update drivers manually

Generally speaking, device manufacturers always want the hardware they produce to work on newer computers and later versions of operating systems. Hence, they release updated versions of hardware drivers for these devices which they place on their websites.

As long as you know what you are looking for, you can proceed to the manufacturer’s website to download the latest hardware drivers for the devices on your computer. You will need to ensure that the name and model of your hardware corresponds to the driver you have downloaded. Moreover, you must make sure that the driver you downloaded is the right one for your operating system.

It sounds like a lot of work, especially if you’re updating multiple device drivers developed by different manufacturers. This is compounded by the fact that some of these OEMs are hard to track down online and the drivers you are looking for might be tucked away in some obscure corner of their website. Even so, as long as you have the will to put in the effort, you will most likely get what you need in the end.

Once you’ve downloaded everything on your computer, click a driver file and let the installer guide you through the installation. You might have to extract the driver file from an archive first before you can proceed with the installation. Repeat the process for each downloaded driver file.

  • Update drivers automatically

The previous method sounds like a lot of fun, doesn’t it? It seems like an awful lot of time spent chasing files that are no larger than a few megabytes at best. If you don’t want to expend all your energy on what might turn out to be a wild goose chase, you can automatically bring your drivers up to date with Auslogics Driver Updater.

Auslogics Driver Updater is a safe, fast, and intuitive tool that updates all drivers on your PC in one click to prevent device conflicts and ensure smooth hardware operation. It will give you a report on outdated or missing drivers it detects, and let you quickly update them to the latest manufacturer-recommended versions.

Here is how to use Auslogics Driver Updater:

  • Download and install the software.
  • Launch Auslogics Driver Updater and connect your PC to the internet.
  • Click the green “Start Search” button and Driver Updater will search your system for faulty, missing, and outdated drivers.
  • A list of drivers that require updates will be shown by category. Click “Expand list” to view them all.

If you like what you’ve seen, you can upgrade to the full version. It will scan your devices and update them all with a single click to ensure smoother performance.

It is always recommended to bring all the drivers on your machine, and not just the ones for your portable devices, to the latest versions You might think a certain hardware driver might be the culprit and want to update just that one, but updating everything saves you from regret if you’re mistaken. Moreover, it replaces other problematic drivers that will eventually bring more annoyances later.

Final Words

The CMUSBDAC.sys SYSTEM_THREAD_EXCEPTION_NOT_HANDLED blue screen of death error is an example of how a seemingly small issue can cause huge complications like a BSOD loop. In the worst-case scenario, some affected users had to resort to reinstalling Windows 10 completely. However, with the fixes we have provided here, chances are you won’t need to turn to such a drastic measure.