Is it just me, or has Turkey been the problem child lately in NATO?  Does NATO have any tools to punish bad behavior of its members, short of outright expulsion?  Does each country get an equal vote in decision making, such as tiny little Iceland, which has almost no military or economy compared to the US or UK gets the same influence in decisions?

Can you elaborate of what you feel Turkey has done or is doing?

They are buying the S-400 missile system from the Russians.
This has led to tension with the US, on top of the already present accusations that the US is harboring enemies of the Turkish state, and the fact that they have the most imprisoned journalists of any NATO member state,

The missile system purchase has brought several threats from the US, that Turkey will be disallowed from buying F-35s.

Problem of Turkey and its people is Erdogan.. yet another dictator-to-be.. Like disease spreading on the entire world..

Plus there is still the Cyprus situation straining relations with Greece, and the Kurd situation straining things with the US.   This kind of thing might not be new to NATO.  I am unsure if Franco in Spain might have done some dictatory things.