Why can I hear a meeting but record silence?

Safety first: Finish any active recording before switching audio devices. Windows and conferencing apps can send sound through a different playback endpoint from the one selected for capture; Bluetooth stereo and hands-free modes are a common example. Check Windows output, the meeting application output, and MazKir audio selection. Test with computer speakers, then review a short recorded sample. Restore your original device settings if the test does not help.