Interponen comes from the verb interponer, meaning to interpose, to interfere, or to get in the way. It is a more formal and less common word than simple verbs for blocking or stopping something.
La Maquinaria Norteña sings "Yo sé que incluso se interponen el" (I know that they even get in the way), using the word to describe outside forces or people who keep interfering with the couple's relationship.
This song, "Decide" by La Maquinaria Norteña, is all about a person who's had enough of someone playing games with their feelings. They're tired of the uncertainty and the lies, saying, "creo que tú estás jugando con mis sentimientos" [I think you are playing with my feelings]. It's clear they see through the deception, noting, "veo en tus ojos es la mentira cuando dices te quiero" [I see the lie in your eyes when you say 'I love you'].
The singer is putting their foot down and demanding a decision. They're not going to let this game continue, stating, "no voy a permitir que siga este juego" [I'm not going to allow this game to continue]. It's a powerful message about valuing your own time and emotions, because, as they say, "el tiempo... hoy ya se está terminando" [time... today is already running out] for the love they have to offer. It's a blunt and honest call for clarity!