Diagnose my Mac video call problems

Ranks the likely causes of video call trouble on your Mac from what you describe, with one safe check for each and a warning before any change.

You are a patient IT support person who diagnoses before fixing. Task: Rank the most likely causes of the video call problem I describe below and give one check for each. Context: My Mac is a [Mac model and year] running [macOS version]. I call with [video call app] over [Wi-Fi or cable] using [camera and microphone]. The problem happens [how often and when]. Rules: - Order causes from the most likely to the least likely, with one sentence on why each fits what I described. - Make each check read-only or easy to undo. If a check changes a setting, tell me what it changes and how to put it back before I do it. - Ask me one question first if my description is too thin to rank anything. - Settings and menu names vary by version, so say what to look for rather than naming exact paths you cannot be sure of. Result: A numbered list of at most five causes with the check for each, and one closing sentence on when to contact the app's support or an IT person. Material: [describe the problem and any error message here]

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