SYSTEM_THREAD_EXCEPTION_NOT_HANDLED (CMUSBDAC.SYS) is a BSOD that has been bothering PC users since the release of Windows 10 cumulative update KB4016635. The blue screen of death usually occurs when using a USB microphone. However, it has also been reported to occur when playing games, downloading updates, or immediately after a system reboot.
According to some experts, the CMUSBDAC.SYS error may be caused by faulty update components. However, others claim that the main reason for the interruption is a virus/malware or a corrupt C-Media USB Audio Class Driver. Unfortunately, the bug continues to cause problems for users around the world.
In fact, the CMUSBDAC.SYS file is associated with the C-Media USB Audio Class Driver. The file itself cannot be deleted or modified because it is part of the Windows I/O subsystem.
Like most BSODs, the CMUSBDAC.SYS Stop error can be extremely annoying, especially if the user is not a technology expert and has only a basic knowledge of Windows operating system maintenance. It usually occurs 5 or 6 times a day, which is a lot considering that every time the SYSTEM_THREAD_EXCEPTION_NOT_HANDLED (CMUSBDAC.SYS) error appears, the system has to reboot.
Unfortunately, there are no official solutions yet, but you can try to get your PC back up and running. As we said before, the problem of these errors may be related to malware infection. Therefore, you should perform a full system scan before trying methods to fix the error.
What causes CMUSBDAC.sys Blue Screen of Death?
C-Media Audio Class incompatibility: If the C-Media USB Audio Class driver is currently active on your computer (after upgrading from Windows 7 or Windows 8.1), you can solve the problem by using Device Manager to remove it and replace it with common equivalents.
Blue Snowball microphone conflict: If you are using a third-party Blue Snowball microphone in Windows 10, the driver it should use by default (which belongs to the C-Media infrastructure) may not be fully compatible with Windows 10. In this case, you must install the Asio3All driver package to resolve the conflict.
Completely outdated motherboard drivers: It turns out that one of the most common reasons for this behavior in Windows 10 is that the motherboard and/or chipset drivers are severely outdated. In this case, you can fix the problem by updating the drivers through official channels.
How to solve the blue screen of death CMUSBDAC.sys?
Perform a system restore
If your system has been updated or you have installed new programs on your computer, the new updates may not be compatible with your computer and the CMUSBDAC.sys blue screen may appear.
- Click the “Start” button in the lower-left corner of the screen and type “recovery”.
- Then click on Restore in the list of results.
- Click Open System Restore to open the System Restore Wizard.
- Follow the System Restore Wizard to restore your system from a system restore point.
- After system restore, restart your computer as usual and check if the blue screen error is resolved.
Reinstall the C-Media USB Audio Class driver
Since the CMUSBDAC.sys blue screen error may be due to a problem with the C-Media USB Audio Class Driver, you can uninstall and reinstall the driver to solve the problem.
- Press the Windows logo and R keys on your keyboard simultaneously to bring up the Run dialog box.
- Type devmgmt.msc and click OK.
- Double-click Sound, Video, and Game Controllers to expand the category.
- Right-click on the C-Media USB Audio Class driver and click Uninstall Device.
- Then follow the instructions on the screen to complete the uninstallation.
- Reboot your computer.
- Go to the manufacturer’s website to download and install the C-Media USB Audio Class driver on your computer.
- Reboot your computer after reinstalling and check if the CMUSBDAC.sys blue screen has been restored.
Scan for Viruses and Malware
Perform a virus scan on your entire Windows system. Yes, it may take some time, but it is worth it. Unfortunately, Windows Defender may not detect the virus. Therefore, it is worth trying another antivirus program.
- If malware is detected, follow the instructions of the antivirus program to remove it.
- Then restart your computer as usual and see if that solves the blue screen problem.
CMUSBDAC.sys blue screen may appear if your system is infected with viruses or malware.
Frequently Asked Questions
CMUSBDAC stands for C-Media USB DAC Device Driver. Any small problem with this driver can cause a blue screen of death with the error message SYSTEM_THREAD_EXCEPTION_NOT_HANDLED stop. The driver may be out of date or corrupted.
If you have system restore points that were created before the blue screen of death appeared, you can fix the problem by performing a system restore. If you cannot access your Windows and its desktop, Windows will automatically start what is called recovery mode after several systems reboots.
- Reinstall the C-Media USB Audio Class driver.
- Update existing drivers.
- Scan for viruses and malware.
- Restore your system to a restore point.
- Right-click on This PC.
- Go to the Properties section.
- On the left side, click Advanced System Settings.
- Under Start and Recovery, click Settings.
- Now in the System Errors section, uncheck Restart automatically.
- Click Ok to save and continue.