[Explanation?] German joke

I've just overheard a german telling a finnish guy a joke and I didn't understood it. Can someone explain it to me?

* *Which players in an orchestra can't you trust?*
* ...
* *The finnish*

You might also enjoy

Many of the jokes are contributions from our users. If you find anything offensive and against our policy please report it here with a link to the page. We will do everything to make this an enjoyable platform for everyone.