Microphones can distort for a number of different reasons. The best place to start is by checking the distance your microphone is from you. Also, ensure that your OBS filters are configured correctly. You can reduce the gain setting within OBS if you find there is too much by default. If you are streaming in an outdoor environment, keep in mind that some microphones are susceptible to distortion when exposed to wind. A solution to this problem would be to purchase a windshield if you often stream in challenging environments.