They could easily jitter audio/video frame delay, or the codec noise in the video (main and delta frames, quantization, colour gamut) per receiver. If it is sha

They could easily jitter audio/video frame delay, or the codec noise in the video (main and delta frames, quantization, colour gamut) per receiver. If it is sharing a document view it could jitter the pixel colour (like a printer dither) or the position of characters. It's basically impossible to be sure, though if you had multiple endpoint recordings you could probably identify likely deltas. Examining the state of the zoom client might also be useful, because it is free to do this client side. Unless the IDs are cryptographically generated server side, you could tweak the client side to show someone else's client ID.