Really loud echoing as the host that only I can hear... help

[RachelU]

I have been using Zoom for 1 on 1 meetings with my students for the last 2 years on my all in 1 PC desktop. I do not have external speakers nor an external mic. There is no one else in my office so no other computers or speakers near me. I use the original sound for musicians and no noise cancelations since I need to make sure we both can hear softer sounds such as /k/ and /th/. Everything has been smooth up until a few weeks ago when my voice started echoing like crazy. My students can't hear it on their end, and they don't echo, only I do ( on my computer only). I have updated drivers, used head phones, played around with mic and speaker volume , as well as played around with some of the zoom sound options... nothing has helped....... any suggestions?