The phone was out of whack.
whack是个拟声词，读音仿佛激烈碰撞时那种惊天动地的声音。out of whack这个短语的正确意思是：“紊乱，不正常”。因此，当美国人说"The phone was out ofwhack."时，他/她要表达的意思就是:"The phone wasbroken."、"There was something wrong with thephone."、"The phone was out of order."。
Benjamin: Hello, Terry. What's up? Why are youcalling me so late?
Terry: Ben, I tried hundreds of times to contact you this afternoon, but failed.
Benjamin: I'm sorry. The phone was out of whack.
①So I missed a few important calls.
②So call him back later.
③Well, you can try this one.
④Oh, I'll ask someone to have it repaired.
whack n. 重击
You really have to whack the ball.
Someone whacked him on the head.
We got whacked. On paper we should have wiped the floor with them.
His mother was murdered. Yeah, she got whacked. Snuffed out.
The ecosystem will be thrown out of whack.