At the risk of stating the obvious, I want to state the obvious: music itself can change my mood. Even if I can't understand the lyrics, or am in a different state of mind altogether, when I hear certain chord progressions, I am moved, against my will, so to speak. Sometimes, even in a genre I don't like at all, a voice sings a note or an instrument produces a sound that brings tears to my eyes, I am so moved. I may feel disgusted that I get teary over some song I hate, but I cannot prevent it.
Sometimes I feel manipulated by music, so I have to be very careful about what I listen to. Movie music is designed to manipulate, as most people know intellectually, but when I am immersed in the movie, the music tells me what to feel and I automatically feel that, unless I am able to remain outside the movie for whatever reason.
I remember when I was a teenager there was an Urban Legend claiming that people committed suicide after hearing "Gloomy Sunday". Who knows? If they had stopped the song, and played an upbeat tune, could they then have run out into the sunshine, frolicking in daisy fields?