microphone issue

i am using zoom from last 3 years or so from by desktop with lenevo 300 fhd webcam. the problem is with my voice it works well, but when mic is exposed to a good blue tooth speaker the sound distorts or stop being reproduced to the participants. what is to be done. Even sharing a computer sound via youtube is also fine sounds good. the problem is with speaker when kept close to the mic to play. it becomes a mess. pl. suggest some solution. could it be webcam issue...