APO equalizer not working (Won't start)
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#338 APO equalizer not working (Won't start)
open
nobody
13 hours ago
2026-01-16
No
After installing different versions of APO Equalizer 1.4.2), it won't start. It simply won't start. "Wir+R - eventvwr" shows the following errors:
Faulting module name: DeviceSelector.exe, version: 1.4.2.0, timestamp: 0x67dd75bd Exception code: 0xc0000005 Error offset: 0x0000000000026d34
Faulting module name: Editor.exe, version: 1.4.2.0, timestamp: 0x67dd75e5 Exception code: 0xc0000005 Fault offset: 0x000000000000856b3
I tried disabling all drivers, completely deleting everything that could work with sound, etc., nothing works.
Was this at the initial installation of Equalizer APO? Or did it suddenly stopped working after some time?
Just registered to report the same issue.
Fresh, first install of Equalizer EPO.
Both Device selector and Editor. Same when opting "Run as administrator"
Windows 11 Pro 25H2
Sound card FiiO K9
Faulting application name: DeviceSelector.exe, version: 1.4.2.0, time stamp: 0x67dd75bd
Faulting module name: DeviceSelector.exe, version: 1.4.2.0, time stamp: 0x67dd75bd
Exception code: 0xc0000005
Fault offset: 0x0000000000026d34
Faulting process id: 0x20CC
Faulting application start time: 0x1DCAB333E11DED1
Faulting application path: C:\Program Files\EqualizerAPO\DeviceSelector.exe
Faulting module path: C:\Program Files\EqualizerAPO\DeviceSelector.exe
Report Id: 5a07ae69-80ef-4f72-b797-72d0f4bcabdf
Faulting package full name:
Faulting package-relative application ID:
Faulting application name: Editor.exe, version: 1.4.2.0, time stamp: 0x67dd75e5
Faulting module name: Editor.exe, version: 1.4.2.0, time stamp: 0x67dd75e5
Exception code: 0xc0000005
Fault offset: 0x00000000000856b3
Faulting process id: 0x1F88
Faulting application start time: 0x1DCAB331B31ACC8
Faulting application path: C:\Program Files\EqualizerAPO\Editor.exe
Faulting module path: C:\Program Files\EqualizerAPO\Editor.exe
Report Id: 41e6652e-e019-4831-8f01-425cc399df13
Faulting package full name:
Faulting package-relative application ID:
Last edit: George 2026-03-03
If this is a problem of corrupted registry key values in which the editor settings are stored you could use my Equalizer APO issue solver. This is issue in this app which is solved by deleting these key values so the editor creates them again at its startup.
tried that, no fix.
Although it is understandable since there are no registry values to be corrupted. The editor and device selector, never did run, they crashed immediately.
Then it's about one or more removed audio devices of which the registry still has an entry. This can also be checked with the Equalizer APO issue solver (issue 7). It tries to detect this. Unfortunately this app can't correct this, especially knowing it's a tricky one to correct. One needs to use a good Windows registry cleaner or the Windows utility bdism.exe or even both.
Thank you for the suggestion. Unfortunately it did not work.
Even though "Equalizer APO issue solver" showed no error (attached)
I went through the painful task of cleaning my registry, advanced run regedit (run as trustedinstaller) under:
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\MMDevices\Audio\Render
deleted 22 ghost devices and left only the active ones.
still it crashes with the same error..
Wow, 22 ghost devices. That seems a lot.
So there is yet another issue which my solver hasn't covered. I wish the developer would react on this matter. Unfortunately I don't know what it is about. There is the rare occasion of an overactive anti-malware app but I don't that's it. VirusTotal doesn't show anything on the editor nor on the device selector.
Another equally rare is the crashing due to an issue of certain Windows updates. Are you on the Windows Insider Program for receiving the newest updates? Also, I suggest to switch off the "Get the latest updates ..." switch. In the past this got Equalizer APO users into problems although it did only happen for some Windows updates.
Mostly audio devices from my 2 monitors connected through hdmi/displayport. Every time Nvidia GPU drivers update, those devices refresh...a couple old mic drivers from old cameras, and 1 old FiiO K9 device from when I changed the USB port. They all add up in the end.. lol
No insider program. Latest "non preview" updates in Windows 11 Pro. Feb 26 as of now.
Using Eset as AV. Even though no logs of blocking anything on Eset, I tried disabling it together with Windows defender, but to the same results.
Good to try but that was to be expected.
What happens when you start up the computer with the FiiO K9 disconnected? Same issue? Perhaps even uninstalling device drivers, just to see which one is the culprit when you install them one after the other. Anyway, when saying "mic drivers from old cameras" this could present a problem. I wish there was an easier way to do this all but I can't think of any.
already tried with FiiO K9 disconnected.
mic drivers from old cameras were cleaned along with the other ghost devices.
did not uninstall all audio drivers.
Some I can't, like hdmi audio from monitors.
For the other drivers, it is too much work, and if that indeed is the culprit then the software won't work for me...
Still I do not believe it is the drivers, FiiO is a widespread vendor, which many audiophiles use..
oh well, I gave it a try, lol.
maybe I'll try next version, or if the developer wants to jump in...
Thanks for the support.
No problem, George. Indeed, perhaps the next version.
I had the exact same crash (Equalizer APO 1.4.2.0: DeviceSelector.exe offset 0x26d34, Editor.exe offset 0x856b3). A Process Monitor trace of DeviceSelector.exe showed that right before the crash it looks up the Startup known folder and fails to open %APPDATA%\Microsoft\Windows\Start Menu\Programs\Startup (NAME NOT FOUND); the process dies about 1 ms later with 0xC0000005. That folder was missing on my machine (shell:startup also failed). Recreating it with mkdir "%APPDATA%\Microsoft\Windows\Start Menu\Programs\Startup" fixed both Device Selector and Editor for me. Worth checking if that folder exists on your system. A similar fix was mentioned in ticket #208.
Yes, that's one of the few things that makes both app crash. This issue is included in my Equalizer APO issues solver. It solves this by creating the user start up folder, just like you suggested. Btw. Thanks for sharing your solution. What I don't understand why this folder isn't there or why it gets removed (by Windows itself?).