Audio delay (lip sync issues where audio doesn't match video) on video calls is caused by network latency or Bluetooth codec delays. For network-caused delay: switch to Ethernet, close bandwidth-heavy apps, and test your latency — anything over 200ms will be noticeable. For Bluetooth delay: the HFP/Hands-Free codec used during calls adds 100-300ms of latency. Switch to wired headphones for zero-latency audio. Some wireless gaming headsets use 2.4GHz dongles instead of Bluetooth and have much lower latency. In your meeting app, lower the video resolution to reduce processing delay: in Zoom uncheck HD in video settings. Close resource-heavy apps to free CPU — video encoding and audio processing compete for resources. On Windows, set your audio output sample rate to 48000 Hz in Sound settings > Properties > Advanced to reduce processing overhead.
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