在系统设置里确认浏览器/应用已获麦克风与摄像头权限。插上耳机后，把 Teams 的扬声器与麦克风都选成该设备，可减少回声。若声音很小，先看系统音量与静音键，再看会议内设备菜单。
开会前：麦克风、摄像头、耳机怎么检查
Before meeting: mic, camera, and headset checks
Grant mic/camera permission in system settings. After plugging in a headset, select it for both speaker and mic in Teams to reduce echo. If audio is quiet, check system volume and mute, then the in-meeting device menu.