No, hydralic tappets will make noise too.
Have you considered an engine flush.
Some people add ATF to the oil about 100 miles before the engine  
oil change.  Me, I'd rather pickup the correct engine flush
fluid at my local auto arts supplier, follow the instructions.

Here in Australia, under certain conditions, the tappet rails, can get
clogged with rubbish, as th eother guy said, a good flush out often stops
the clicking noise. Then again,  could be a few new seals and gaskets needed
as well, depends on how many kms the engine has done to date.

Peter