Problem: When starting a call, I often don't know if the system is using my high-quality desk mic or my laptop's built-in mic. Currently, I have to wait for the lead to tell me "I can't hear you well" before I realize I'm on the wrong input. Proposed Solution: Add a real-time mic activity bar (visualizer) and a quick-switch dropdown directly on the call interface (e.g., System Mic vs. External Headset) without leaving the call screen. Benefit: This ensures professional audio quality from the first second of every call and prevents awkward "Can you hear me now?" starts.