“Telephone” by Gaga/Beyonce is about Mycroft dancing in a club, with his snifter of brandy, getting pissed off because Sherlock keeps calling him to talk about cases.

Just a second, it’s my favorite song they’re gonna play
And I cannot text you with a drink in my hand, eh…
You should have made some plans with me, you knew that I was free.
And now you won’t stop calling me; I’m kinda busy.
Stop callin’, stop callin’, I don’t wanna think anymore!
I left my hand and my heart on the dance floor.
Stop callin’, stop callin’, I don’t wanna talk anymore!
I left my hand and my heart on the dance floor.
…
Can call all you want, but there’s no one home, and you’re not gonna reach my telephone!
Out in the club, and I’m sippin’ that bub [brandy], and you’re not gonna reach my telephone!
…
Boy, the way you blowin’ up my phone won’t make me leave no faster.
Put my coat on faster, leave my girls no faster.
I should have left my phone at home, ‘cause this is a disaster!
Callin’ like a collector - sorry, I cannot answer!
…
Tonight I’m not takin’ no calls,
‘cause I’ll be dancin’.