I had this exact same issue and it drove me bonkers for ages but I finally managed to fix it.
For me the issue was being caused by the Dell in built audio software which is "MaxxAudio Pro (Waves)" when I opened the software I got the following screen:
What i had to do to fix this is:
- Connect your external microphone
- The microphone icon in the screen then becomes "selectable"
- Click the microphone icon
You then get presented with the screen above (this screen is NOT selectable until you connect an external mic (or it wasn't for me))
- Then click on the "Remove Noise" toggle switch to turn it OFF
- Then click on the speakers icon and do the same
These steps prevent MaxxPro software from automatically removing the resonant background sounds you get from instruments, bells, ringing etc and allows other software packages to process the audio signal "as is".
The issue for me was that this is automatically turned ON by default in MaxxPro and you must first connect an external mic to even be able to interact with the buttons to turn it OFF. It was driving me mad because people were suggesting this could be the problem but I couldn't figure out how to disable the signal processing done in MaxxPro.
This 100% solved my issue and allowed conferencing software such as Zoom etc to use the "original sound for musicians option" in it's intended way. The issue is that MaxxPro etc. seems to take priority and you must disable the automatic sound removal there to allow Zoom or Teams to do it's thing.
Your laptop may have different sound processing software but the process should be the same - i hope that fixes it for you!