Various high-pitched ringing noises after sounds are played

I use my headphones whenever I use my laptop, and the headphones aren't causing this problem (I tried them on my phone and other computers). I have laptop that, for some reason, plays high-pitched ringing after a sound is played (like a video or notification) and the ringing won't stop until another sound is played. The ringing doesn't happen when a sound is played, just after. This only occurs when I use the audio jack, so I've been using a USB-to-audio jack adaptor for the past few months to escape the ringing. The ringing varies in tone, but it's always high-pitched. Here's a crude example

eeeeeeeeeee *notification sound* EEEEEEEEEEEE *music plays* eeeeeeeeeeeeeeeeeee *silent moment in a movie* EEEEEEEEEEEE

Does anyone know what could be causing this? Again, it's just the audio jack. If I use an adapter to use my headphones, there's no ringing. The drivers are all up to date. The audio driver is the Synaptics Audio from Microsoft (version 10.0.18362.1). There's also a program called SmartAudio 3 installed

Laptop: Acer Swift SF514-54T
Windows 10 Version 1909

Jacee said:

In your system settings, go into system sounds and see which might be set and turn them off.

I not sure what you mean, but the high-pitched ringing is not a sound designed for Windows. It's like there's a problem with the driver or whatever. It's constantly ringing whenever sound is not being played. Most of the time the ringing is barely audible, but it's still constantly there. It's tough to describe the sound, but it's in the 4000-6000 Hertz range like in this video but much softer and quieter CAN YOU HEAR THIS - YouTube. It keeps varying each time too. It'll be barely audible, then a notification goes off, then it changes and becomes very audible and stays like that until another sound is played then changes again. It's very bizarre

Sounds like feedback - either from a mic or internal. I just managed to reproduce this oscillation by checking 'listen to this device' under stereo mix - listen tab.

The same thing happened on my grandmas new lenovo computer. I can't recall the exact model, however, after spending hours of troubleshooting, we gave up and simply re-installed windows which fixed the issue.

As mentioned in post #5 this is feedback.
A combination of settings mainly gain/volume on inputs from a source(s) like a Mic, Line input(s) and possibly added sound effects(or enhancements) may produce this.
Of course re-installing Windows will fix it as settings will be restored to sensible defaults, but that is vastly over the top and you learn nothing from that.