A microphone test often sounds good because the speaker sits very still. During the real interview, that person turns toward notes, laughs or leans back. The result can be a voice that changes level every few sentences. Test normal movement as well as normal speech.
Choose a position you can keep
Start with the microphone close enough to capture a clear voice without forcing the speaker to lean forward. The best distance depends on the microphone and room. Use its maker's instructions as a starting point, then make a recording rather than treating one distance as a rule for every microphone.
Say the same sentence three ways: facing forward, looking at your notes and turning toward the guest screen. Listen for changes in level and room sound. If the notes position is much quieter, move the notes closer to the microphone's direction instead of immediately adding more gain.
Leave room for a real conversation
Check that the microphone stand does not block the screen or make typing awkward. A position that is uncomfortable will not stay consistent for a forty-minute conversation. Place water where it can be reached without moving the stand. Keep paper away from the microphone body.
For a remote guest, describe the result you want: a steady voice level and comfortable posture. Avoid a long list of recording terms. Ask them to send or replay a short sample before the interview.
Do one final test with a louder sentence and a small laugh. Set the input so these moments still have space below clipping. A stable physical setup reduces the amount of repair needed later.