Boombox Party

Boombox Party says fruit can turn Disco, without the 'small chance' wording that Disco, Disco Party and DJ Sam use. Disco is a x125 mutation, and the wiki lists Boombox Party in a long set of conditions: Disco, Monster Mash, Super Storm, DJ Sam, Text Collect, Boombox Party and Strobe Party.

That makes it one of the named routes to a x125 multiplier, alongside the Disco Bee pet and the Mutation Spray Disco. The entry mentions no growth bonus, rewards or timing, so what is known comes down to the Disco roll and the party theme.