Yeah, it scares me too. But at this time of year its a bit of a struggle to get anything done.
Funny though, iv had the car coming up two years and its done it since day one that i can recall.
I will get the parts i have swapped over etc and will report back as soon as i do. Hopefully with good news
Was there anything else i should change that COULD be causing the then noise while im at it?
Currently have
Waterpump
Tensioners
All Belts
Seals
I guess before i start i could try whipping the belts of temporarily too, just incase its some random pulley.