High CPU Usage cxuiusvc64.exe is the culprit

Hi.

Version 20H2 (OS Build 19042.928)

So my problems started a few days after the last update; 2021-04 Cumulative Update for Windows 10 Version 20H2 for x64 based Systems (KB5001330).

I have Piriforms Speccy installed and it reports the cpu temp is around a constant temp in (F) of about 148-152 degF. If the temp goes above that the fan goes into high gear. I've seen the temp raise as high as 171 degF. In fact it's ramping up as I type this, then about a minute later it will subside. It's basically a roller coaster all day long.

If anyone has any ideas I'd love to hear them. I tried searching on cux.......64 but got no replies. If you need more screenshots let me know.

Thanks.

The genuine CxUtilSvc.exe file is a software component of Conexant SmartAudio II by Conexant Systems.

If you instead search on cxu...64 you will find various people having issues - but not recently. I would first stop and disable the service (to avoid the overheating), then scan the .exe with something like malwarebytes. There are reports of a keylogger which shipped with some HP laptops a few years back (a faulty Conexant driver) - see How to Check if Your HP Laptop Has the Conexant Keylogger

It seems unlikely to be that, but it suggests Conexant have some code quality issues. Of course, the .exe may be malware posing as a legitimate program.

Thank you both for taking time to reply.

I was able to determine that the program is from Conexant Systems but couldn't figure out how it got in the computer. More confusing was is that this computer is not a laptop yet all topics referred to it being a laptop issue. As I noted the problem showed up after the listed update. Maybe it got in some other way and we just like to blame updates for our problems.

I ended the process and the cpu usage went from 87% to the current 22%, and from 160 degF to 102 degF. Shutting down and restarting was successful as the program did not reload it self. So we appear to be good.

Now there's a file running at 16% of cpu but that's for another topic which will be posted shortly. But even with the other process using 16% cpu, the temp is only 102 degF and no fans are screaming.

Rep coming for both of you.

glad to help (not that I did!). If it starts again, disable it and see what doesn't work...

mngerhold said:

If you instead search on cxu...64 you will find various people having issues - but not recently. I would first stop and disable the service (to avoid the overheating), then scan the .exe with something like malwarebytes. There are reports of a keylogger which shipped with some HP laptops a few years back (a faulty Conexant driver) - see How to Check if Your HP Laptop Has the Conexant Keylogger

It seems unlikely to be that, but it suggests Conexant have some code quality issues. Of course, the .exe may be malware posing as a legitimate program.

maybe look for some updated Conexant audio drivers that not only fixes the "keylogger" problems from either the manufacturer (or like the 2020 versions from MUC) but are also compatible with 2004/20H2/21H1.

also note that the KB5001330 update for 2004/20H2/21H1 seems to be causing some performance issues as noted here.

Windows 10 20H2
I found the same problem. It may have been caused by a piece of software I just installed (now uninstalled).
I just stopped the service after uninstalling and then started and so far its running at very low speed.
Not sure if the piece of software I installed was the culprit or not so I won't mention its name.
I scanned CxUIUSvc64.exe with malwarebytes but it didn't find a problem. However in the services app there is no description for the service which makes me slightly suspicious of it.

I have the same problem o a Lenovo P53 laptop.
The CxUIUSvc64.exe (part of CxUIUScv Service) is having 100% CPU.

This is not the first time. Stopping and restarting that service "fixes" it. Until it happens again.

Interesting, according to Device manager, my audio is Synaptics Audio. Did they buy them?
Aha, wikipedia says: The company was acquired by computing interface technology company Synaptics, Inc. in July 2017.

I just checked again and CxAudioSvc is running at very low so problem has not re-occured for me.
Windows 10 Pro 64bit 20H2
I also have
Synaptics HD Audio
Driver Date: 2020-09-14
Driver Version: 8.65.319.150