Greg.

Greg.

Digitals do not sound like acoustics.  None of them, you play them side by side and you'll see/hear that.  Some think they come close.

Comparing P'teq with a digital is wrong.  You need time to make that adjustment.  Took me until now; i bought it 4 or 5 years ago!

Doesn't seem right that system-wide disabled drivers still show up in ASIO4all settings

SO many things it could be. Pianoteq doesn't seem the logical cause of this - but have you tried uninstalling it and reinstalling it. (less hassle than a reformat and reinstall of OS etc - especially not fun this time of year).

My first thought now is about where you say "speakers into amp" - are you plugging speakers out of 'line out', and headphones out of a 'headphones' at the same time? Or do you have an external audio unit involved?

An external audio unit has advantages if you have more than one thing plugged in at a time. You may already have done this, but certainly try only having one thing (speakers OR headphones) plugged into PC at a time to see if that's helpful.

Also - it just may be that one of these is coming out of the wrong output (or an inappropriate output). For example, some systems may have "Line Out" AND "Headphones" AND "Headset". Obvious what line out may be for right? But the others?

So before anything else, just quickly check if one of these outs, is also for headSET (which includes 'services' for a headset with microphone for telephony/gaming etc). That may explain the change when differentiating your input and playback.

Maybe, just maybe, when "handling input" (your playing) some 'dumb' service is trying to read/handle this signal 'as audio' rather than midi. Then when just playback, theres NO 'headset' microphone system in the way leading to the correct audio path.

Could be that this is also further related to one of the below..

a,
something else could be back-loading drivers from a previous install (clutter left behind after uninstall maybe). I'd comb through programs to see if there's something forgotten or not properly uninstalled before anything more drastic like reformat and reinstall of OS etc.

b,
if you have a PC with an ensemble of OEM features - these may add some layers (like home theatre Dolby 5.1 etc. and entirely separate but 'integrated' settings and features) into the mix. Although that layer of 'extras' may never get in your way visually inside settings, some of these 'services' can surface at times or crash or bork in strange ways.

c,
if you have things like games (or game ecosystems like Steam with their own overlays or features) installed, double-check you're not running it in background with their overlays which might be trying to keep those same 'disabled' drivers loaded. Sometimes elements can clash/crash. Things can go wrong without looking like it. Not singling out Steam for particular reasons (well behaved generally) but sometimes vendors have free reign over your settings sadly. "We know our users love to have always on! live streaming-buddybuddy-chat app for convenience - super excited!".. erm yeah, not if I'm running other audio gear and want to do anything else at all with this machine, kthnxby.

Often the fix is to un-do some unwanted clutter.

I forgot to mention, before you do anything like reformat, it could be good to contact support.

Well, I tried what @Qexl suggested (Thank you so much for such an elaborate response) but I didn't quite manage to achieve what you were saying. I did get to deactivate everything that wasn't necessary, and also unchecked the "exclusive control" option out of everything but my speakers/headphones, but everything was still showing in my Asio4All settings.
The graphics card Nvidia audio drivers were there, everything Realtek related was there... Nothing changed. But when i checked directly the Realtek options only my speakers showed up so that seemed to work. I also rebooted my pc after disabling everything just in case it needed but nothing.

And about Pianoteq, still same muffled sound. Didn't change at all.

I'm beginning to think maybe it's something about my Windows installation/Drivers that went wrong and it's causing this issue. I'll try to format my computer in the next few days and see if that fixed anything. I will post an update.

Thanks everybody for the responses so far, you've all been helpful. Happy holidays!

first close Pianoteq (and other audio apps)

1
right-click the speaker icon in system tray

2
choose 'playback devices'

3
in the the 'sound' window which pops up, you should see the list of audio devices

4
right-click the one(s) you do NOT want to be active

5
choose 'disable' (you can always re-activate them if needed in the same way)

6
load Pianoteq - open settings/midi - open your ASIO4all settings

Now you will NOT see those other drivers.. either 'lit up' or 'greyed out' - they're just not there - no longer getting in the way. So you won't need to 'deactivate' them inside ASIO4all.

Unless I disallow those devices at system level, there seems to be just always be some internal Windows "fight" over these resources - no matter what logical things we set in our programs.

Sometimes Windows just wants to help, a bit like 'Clippy' - often we don't benefit from that kind of "I see you're running two audio drivers, allow me to try to load them both at the same time for you" kind of help It's helpful under some circumstances but not this.

You might also want to check settings relating to "allow this audio device to take exclusive control" - in the list mentioned above, choose 'properties' for any in the list and go to 'advanced' tab, un-select 'allow applications to take exclusive cont4rol of this device' - might help too - make sure the audio device you DO want to use CAN take exclusive control maybe.

I have found time and time again, these are the fix - hope this works for you. Cheers!

Thank you, EvilDragon.

You see, I’m on a Mac and a Yamaha P-95 that is unable to send more than one fixed note-off velocity at any time, as each of my note-offs is a quantified medium or middle standard (64). 

So, maybe I’m just a little jealous!

Anyway, my point is; being a Mac user, I’m unfamiliar with your Windows environment and definitely unqualified to troubleshoot your operating system.

It shows various note-off velocities; some values are maybe higher than actual note-on ones of corresponding notes.

That's quite normal, though. Note-off velocity doesn't have to match the value of the corresponding note-off

I’ve just reviewed the pic you posted.  It shows various note-off velocities; some values are maybe higher than actual note-on ones of corresponding notes.

Have you played with the Pianoteq on-screen Keyboard?  When it’s playable without a hitch, have a good look at your physical keyboard and reset it or connect another MIDI input device and test it instead.  Maybe once your device is set (per its manual) to send just one velocity, conduct your test then.

Since you said it may be a problem with Asio4All, I swaped it to the Windows Audio and the only difference I got was higher delay. Same muffled sound.

Theoretically, when using Asio4All it mutes everything but the program is using it. Right? So it couldn't be that there is something interfering with it from within the OS.

I reinstalled drivers, checked my USB A to B cable to see if it was the problem, unplugged everything from the computer except the headphones, the usb connected to the DP and the mouse... nothing. I even had my family come and compare the sound in case I was going crazy and hearing differences where there weren't. There were.

Are we certain that this is not supossed to happen even with low tier headphones/soundcard?