Region: General | Usage example: After seeing the evidence, she changed her tune about the plan.

Change your tune

Meaning

Shift one's attitude, often toward a previously opposed idea.

Used when someone becomes more agreeable or cautious.

Origin notes can vary by region and source; this page gives the commonly reported explanation and usage context.

Music metaphor for switching melodies to signal new feelings.

Used since at least the 19th century in theatrical contexts and later everyday speech.