This study illuminates the varied emotional mechanisms underlying consumer response to ads paired with emotionally congruent versus incongruent content in different placement positions. This work expands the media planning literature that has narrowly focused on thematic (in)congruency. Focusing on music videos, Study 1 empirically tests the affect regulation effect on consumer response to ads paired with emotionally incongruent music videos and the affect priming effect in congruent pairings. Furthermore, this study incorporates affective computing algorithms to pair ads with music videos based on emotional (in)congruency to advance the emerging field of computational advertising. The results from two experimental studies demonstrate that consumers prefer the emotional flow from a negative to a positive state when the ad and media context are emotionally incongruent. In the emotional congruency condition, regardless of ad position, the positively valenced ad produces more favorable responses. Study 2 further illuminates the boundary conditions of emotional (in)congruency and ad valence, suggesting that consumers’ preference for positively valenced ads in the affect regulation and affect priming processes is more prominent when consumers are less involved. When involvement level is high, negative ads are rated as more persuasive than positive ones. Involvement level also reduces ad skipping, especially when the ad and the media program are emotionally incongruent.