Hacker help: Any idea how to stop a clock from clicking?

Materials: Rusch wall clock

Description: I'm looking for your help. We bought some Rusch wall clock, they're cheap and quite sharp. And, more over, when you don't like 'em, you can easily hack'em.

But.

There is a but.

They're too noisy.
I can hear the one in the bathroom from the bed, and it's like 5meters. Not ensuite. And I have a PC in my bedroom, on most of the nights.

But it tics and tics and tacs.

Any ideas?

~ jo