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What is this ticking noise?

My car makes a ticking noise as soon as I turn the key to the ‘on’ position. The ticking continues once the engine begins running and stops shortly afterward (maybe 10 - 15 seconds). I’ll attach a video of the ticking after the car is already running. I’ve checked the service light. It is the catalytic converter. I’m pretty sure this is a separate problem, but am not sure what is causing it. Can anyone help?

Where…is the noise ?
Quite possibly a heater-a/c blend door

It sounds like it is coming from just behind the dashboard. If I turn it on without the heater/ac on should the noise go away, if it is the blend door?

I tried turning on and off the a/c while it was ticking. No change.