Most musicians don't think twice about their songs being used to pump up the crowd at a sports event. But when it comes to politics, some artists are very sensitive about which leaders use their music on the campaign trail.
British mega-star Adele is the latest in a long string of musicians to speak up about the use of her music, after she demanded Donald Trump stop using her work in his bid for the Republican presidential nomination. Trump had been playing Adele's "Rolling In the Deep" and "Skyfall" at campaign rallies, to pump up the crowd before his appearances.

Adele declared this week that Trump does not represent her values, and asked that he stop using her songs.
And she's not the first musician to intervene about the use of her work. Aerosmith frontman Steven Tyler previously sent Trump a cease-and-desist letter, after Trump's campaign played "Dream On" at a rally. R.E.M. also demanded Trump stop using their music, in a strongly-worded statement last September.  A Trump rally had used "It's the End of the World as We Know It (And I Feel Fine)," sparking the harsh R.E.M. response.
And last June, Canadian rocker Neil Young got into a public spat with Trump, after he complained about the use of his song "Rockin' in the Free World." Young said he didn't want Trump using the song, and Trump replied by saying he didn't "love" the song anyway.
Trump has arguably become the most polarizing figure in American politics these days, but he's not the first politician to cause a stir with his song selection. John McCain, Sarah Palin, Mitt Romney, Nicolas Sarkozy and George W. Bush have all angered artists with their use of certain songs over the years.
CTV political analyst Scott Reid says music choice was once a "superficial" consideration for political campaigns, but now, it's become more complex. Reid says campaigns now have to properly vet the songs they use, or risk being called out in public by a musician who holds views opposite to their candidate's.
"There's two philosophies," Reid told CTVNews.ca. "Go ahead and use it, and run the risk that the musician objects in public. Or seek permission in advance, and risk being told no."
Reid says he did not run into such issues back in the 1990s, when he was an adviser and communications specialist for the Liberals' Paul Martin. Martin would often enter campaign rallies to the tune of "Taking Care of Business," by BTO, because he had a strong background in business, Reid said.
"You want something that has energy, and if there's a message embedded within that song that seems appropriate, then that makes sense," Reid said.
However, he stressed that it's also important to pay attention to the lyrics of a song, so a candidate does not become associated with something inappropriate.
For example, Reid pointed to a musical gaffe involving former Ontario PC leader Mike Harris. Harris once arrived at a rally to the Rolling Stones song "Start Me Up" – a song with a lyric about reaching sexual climax.
Reid said people noticed the inappropriate lyric, and Harris' team stopped using the song as a result.
But, while social media has made it easy for recording artists to call out politicians, the phenomenon is not new. One of the most well-known cases of a performer objecting to the use of his music dates back to 1984, when Bruce Springsteen asked Ronald Reagan not to quote from "Born in the U.S.A."
Springsteen has also asked former GOP candidates Bob Dole and Pat Buchanan to back off from using the song.