I previously had set up a sound for copying (as confirmation "yes, you actually copied that. good job". I don't remember if this is the default setting. Judging by the name of the .wav-file, I don't think so).

Since the 5.0 update the sound is delayed about 3 seconds, which has the opposite of the intended effect.
I have done several fresh installs, both with and without keeping the settings.

The sound is delayed every time and every time by the same amount and it is the same if I copy only 1 symbol or 50.000, but it does take longer if those symbols are formatted:

50.000 symbols with bold, italics, underlined and special characters take about twice as long as 250mio "a"s, but 250mio "a"s take about the same amount as 1 "a".

No, none whatsoever. I also made a completely new rule with only the sound playing (and deactivated the other one) and also one with a different soundfile on a different HDD, and the same phenomenon occurs.

I'm sorry for the long radio silence. Life happened

I attached the log as requested. The text was "This is some random text." copied from Notepad++.

Yes, it does.
Notification and sound are both delayed (by the same amount).

Here you go

Also, I did some additional (unsolicited ) testing:

• In Windows' Safe Mode it seems to work without delay (using only notification, since audio drivers don't load)
• With version 4.2 (newly downloaded via the Old Versions link, but keeping the settings from the current version) it worked without delay.
• I tried shutting down other Applications, that I thought might be the culprit, but no success here.

Oh, boy, you are in for a story of mystery and secrets.

When I previously said, that I had I tried shutting down other applications, that I thought might be the culprit, I had immediately suspected NVIDIA Experience (It's a screen-recording software for NVIDIA-Cards). I specifically love it for the automatic recording of the last few minutes, while also automaticly only recording specific applications (privacy and whatnot).
This is probably where all alarm bells start ringing. "Automatic" "recording" "specific Applications" and the problem has something to do with delay. Sounds suspicious to me, especially because I had other issues with that piece of sh... ...uhm... s...oftware interfering with stuff previously. So I disabled it for system startup.
However the problem didn't go away, so I just shrugged it off and posted my last response.

Now comes today. I read your response and disable ALL THE THINGS. The problem still persists. Having enough of it, I decided to go process by process through my TaskManager to find the culprit. It worked in safe mode so there has to be something running here, that isn't running in safe mode. So I opened ProcessExplorer, my task manager of choice, and who did I see on the very bottom of the page?

NVIDIA Web Helper.exe

Wait, wait, wait. Why would NVIDIA want to talk to the web? The only thing running from them should be the graphics driver and I highly suspect that should be calling back to the mothership.

So I immediately checked for NVIDIA Share.exe, which would be running if NVIDIA Experience would be running (I knew this from the afore mentioned encounters with that application). But only something named "nvcontainer.exe" ran. I didn't know what NVIDIA wanted to contain in there, but it sparked my interest enough that I decided to manually start NVIDIA Experience, just to perform a sanity check. It launched and asked to update (side note: No wait, it just loaded and installed the update. You gotta love things that just update without asking the user. What could go wrong? It NEVER causes problems or has EVER bricked my machine...), which confirmed my sanity: It WAS turned off, otherwise there wouldn't be a launcher window with that update.

But being the inquisitive being, that I am, I just made sure to turn off the Ingame Overlay button (the part of the program that actually records) and tried to copy something.

And it suddenly worked! That sneaky little moth... m...ouse must be getting started from some additional service and disguises itself in the TaskManager.

At this point you might think "Ok, easy fix: Just turn off that overlay and you're good."
But you, dear reader, would be mistaken. You see, I rely on both applications ClipoardFusion AND NVIDIA shadowplay in my daily life. It would've been fine, if it would only malfunction while recording. When playing a game I rarely copy-paste things. But the mere option of being able to record would cause the issue. The entire point was that it records automaticly, remember?

At this point I'm quite defeated. I know the culprit, but I can't do anything about it. I would have to hope that NVIDIA and/or the dear developers of ClipoardFusion fix the issue or I would need to accept that only one of both can be running at a time.
So, I re-enable all the applications for startup, reboot one last time and write my response here. Before posting, I have the habit of copying the post into a text document. I have lost too many hours on rewriting long forum posts, because the post somehow got lost along the way to the server (automatic log off-timers, "hey, there is a new answer, before you started writing you response", etc.). So, I copy my defeat-post and...

IMMEDIATELYTHERE IS THE F'ING SOUND.

I can't believe what my ears are hearing, so I try it a few more times, but there is no doubt: The sound plays immediately. So I perform another sanity check: Yep, the NVIDIA overlay is running. I reboot the machine. Yep, still working.

I don't have words (even though usually I have words. the best words.).
It just works. Maybe the NVIDIA update that loaded fixed it. Maybe I poked somewhere without remembering. Maybe a higher being observed my misery and decided to help me out. I have no clue how or why, but it works.

TLDR: NVIDIA Experience was a bad boy, but it fixed itself. Somehow. idk.