WATCH: Trump paces stage in silence for nearly 20 minutes after microphone goes out at Detroit rally

DETROIT (AP) — Donald Trump walked his rally stage in silence for nearly 20 minutes Friday night in Detroit after his microphone failed.

Watch the event in the player above.

The Republican candidate and former president was about to launch into one of his favorite topics: tariffs, and prepared to name it by first teasing “the prettiest word in the dictionary.” Very quickly after that the sound became quieter.

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The crowd chanted “USA” and “We love Trump” in support. But without a microphone, Trump simply wandered around the stage. He looked frustrated and at times turned his back to most of his audience.

It was the second time in a week that one of his events was interrupted – although the last time, on Monday, Trump shut down a town hall and played music instead after several people in the audience needed medical attention. This time, Trump appeared to have little control over the matter, standing in silence as “Technical Difficulties” and “Complicated Matter” messages appeared on the screens around the room.

Trump is famously attuned to his image and the mechanics of his rallies, often commenting via microphones and teleprompters. Earlier Friday, the hosts of “Fox & Friends” joked that Trump likes to adjust the lighting when he sits for interviews.

Aides have been known to travel with several spare microphones – although it was unclear why they couldn’t immediately find one on Friday – and carefully prepare the flags that adorn his stages.

Vice President Kamala Harris’ campaign used a recent video to spread its message that the 78-year-old Trump may not have the energy to become president again. On X it was posted: “An exhausted Trump walks awkwardly in circles on stage after his microphone stops working.”

As the delay dragged on, the crowd continued to cheer and chant. At some point the crowd waved.

Finally, after nearly 20 minutes, an aide brought Trump a replacement microphone that worked.

“I will not foot the bill for this stupid company,” he said. “I’m not going to pay the bill, and then we have the story that Trump didn’t pay the bill to a contractor.”