zoom and windows 10 - microphone and speaker drop off

I've been having the same problem. I recently replaced my old Dell laptop (which was slow but worked fine in Zoom) with a new Dell. My microphone cuts out in Zoom after a few minutes and people say they can't hear me. The microphone seems to work fine in other apps. I also spent a lot of time going back and forth with Dell trying to fix this issue, and in the end they wanted to charge me for a software consultation. For a brand new computer.

So it's been over a week. I had to teach my course on Wednesday by using my laptop for screen sharing only and logging in under a different Zoom account on my phone for audio. Not a great solution! My issue has been elevated to second level support at Zoom--I don't know if it's the time difference (not sure where the rep is located) but coordinating a Zoom call with the support desk seems to be a problem. I don't understand this because I've replied to his messages within minutes saying "we can meet now" but get no response. Quite frustrating, especially when this does not seem to be an isolated problem.

Still hopeful there will be a solution. Again, my issue is NOT my microphone--it works. It's just the speakers in my Windows/Dell laptop--which work for everything except Zoom.

Same here, Win 10, gaming machine that's a couple of years old with an ASRock Fatal1ty Z270 Gaming K6 LGA 1151 Intel Z270  ATX Motherboards - Intel processor. Sound is handled by the board and there's an NVIDIA driver for sound as well. The sound started fluctuating wildly a couple of weeks ago using Zoom as well as online video with sound, for instance Twitter (Waterfox 64 bit). The sound doesn't drop off it drops to very, very soft which you can hear with the volume turned all the way up for the speakers and the windows control. I've turned off every sound augmentation available under windows and turned off the Zoom sound balance option, no luck. I uninstalled all sound drivers on the machine and let them re-install, sound was good for a few hours then back to wild fluctuations for Zoom.

Some things I've observed;

One on one Zoom meetings haven't been effected, anything more than one or possibly two other attendees and the sound goes crazy.

Games are not effected, sound quality is great and surround is working fine.

VLC is fine, no fluctuations.

Plex is fine, I believe that Plex server uses the local machine for volume control, no problems (please correct me if I'm wrong about that).

Sound is not effected on any of my other devices, Zoom on an android phone has no problems, Zoom on an android tablet has no problems regardless the number of attendees.

This morning I finished one Zoom conference and immediately started  another, the first was fine, many attendees but only one microphone was unmuted, everyone else was muted by the host. The second conference was a free for all, lots of attendees, no limits on microphones and sound immediately went bad again. I looked at task manager and there were three Zoom instances running, two were nested and one was just sitting there like a lump. Killing that process didn't change the fluctuation.

It feels like the Zoom software is having a problem with the potential for multiple sound sources once it sees more than a very small handful of sources.

Problem report to reaffirm what others have said.

I have a hand-built studio desktop (Windows 10) that has run Zoom with my Sapphire external audio without problems. On Saturday (October 3, 2020) I had my first Zoom meeting since September 30, when all was well. I was not hosting the October 3 meeting. The audio output dropped out after several minutes and I had to restart my external audio interface to get it working again.

Today, I was hosting a meeting with students, and the same thing happened. They could hear me but I could not hear them. I had to restart the audio interface.

All other audio applications continued to function.

I am having the same audio problems with my new HP Envy x360 and Zoom meetings. Everything will work fine for a while but then the sound will lock off with either resulting silence or loud buzzing noise. None of the above suggestions has resolved the issue so, if it is a Zoom issue I hope they resolve it quickly.  In the meantime I'm wondering if turning off the Zoom feature to block out background noises would temporarily keep the speakers and audio working correctly? Has anyone tried that? Thanks.