Sound issues on my chrome

 I have a chrome notebook. Im having issues with sound. I can hear the other people in the meeting but they can barely hear me when I use the computer microphone. The odd thing is that that only happens on certain zoom calls. For instance one regular meeting I attend weekly, there are no issues. However on a different meeting they cant hear me and i have to use the dial in option. I went into my settings but really have no idea what to try. Any suggestions?