Participants audio sounds all warbly - can't hear/understand anyone

Hi - I really hope someone can help with this issue.  I have several staff in my office using zoom (ovbiously! lol) but suddenly many started having issues with the sound.  Initially, I thought the external speakers died (it happens) so I replaced them with a USB speaker.  The speakers work great in every other application (YouTube, etc) but in a Zoom meeting, all the sound is warbly and unintelligable.  I've searched for solutions, changed settings, changed ports, everything I could think of and find online, but nothing is fixing the issue.  Everything was working fine a couple weeks ago - I don't know if there was some Zoom update that broke the sound, but I'm at my wit's end!  Thank you in advance for any and all potential solutions!