What is causing this?

I thick the tap sound is the tensioner

but there is also a tick sound from the rappers but I don't think you can here that in the video,

what would cause the tick?
I was thinking the exhaust manifold is causing that sound?

I know pulleys make some sound but it's the tick and tap sound that's annoying
https://m.youtube.com/watch?v=_gwMG1fgdPw

 

I was thinking the tap sound is either the main tensioner or crank pulley
the tension on the belt doesn't seem bad when the car is off but should i change it anyway?

the tap sound goes when you pick up speed
should I replace the crank pulley just in case?
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it's an awkward job as ill be on my back doing it as soon as the weather drys