Things said way too often in the studio, I'll start.

Drummer: "can you turn the click a little bit down?"

me: "sure..."
*pretend to turn knob
me: "is it better?"

drummer: "oh yeah! now it's fine..."
 
Band: "Can we use your drum-set for tracking tomorrow?"
Me: "Sure, it'll cost a bit more and take some setup"
Band: "Yeah that's o.k."

I setup some drum mics the next morning

Band: "Alright let's do this!"
Me:"Where's the drummer??"
Band:"Look!!! We brought a MIDI file"

...bastards:bah:
 
Band: "Can we use your drum-set for tracking tomorrow?"
Me: "Sure, it'll cost a bit more and take some setup"
Band: "Yeah that's o.k."

I setup some drum mics the next morning

Band: "Alright let's do this!"
Me:"Where's the drummer??"
Band:"Look!!! We brought a MIDI file"

...bastards:bah:

If the agreement was over email or text I would have billed them for it. Fuck that shit.
 
drummer: "the drums aren't loud enough"
guitarist: "the guitars aren't loud enough"
singer "the vocals aren't loud enough"
bassist: "the bass isn't loud enough"
everyone (except the bassist): "shut the fuck up n00b"
 
drummer: "the drums aren't loud enough"
guitarist: "the guitars aren't loud enough"
singer "the vocals aren't loud enough"
bassist: "the bass isn't loud enough"
everyone (except the bassist): "shut the fuck up n00b"

True story; after a week of dealing with that during a mix down I burned a mix for each band member with JUST THEM respectively.
Then told them when they got over their fucking narcissism we could address my narcissism when I give them the mix I want to do.