The Ol’ Jitterbug
well, you aren't bugging me, so jitter away.
The Ol’ Jitterbug is the 71st track of the DELTARUNE Chapters 3+4 OST. It plays on the gramophone when entering the Dreemurr residence after sealing the 3rd Sanctuary Fountain. It is the accompanying music to Toriel and Sans dancing the "jitter bug".
- The song uses the first part of the Ghost Fight leitmotif, first seen in Undertale.
- Kris has the option to "Change the RPM" when interacting with the gramophone, speeding up the song by 36%, though this is not reflected on the OST. An increase in speed by 36% roughly corresponds to the increase in turning speed that happens when a gramophone is switched from 33 RPM mode to 45 RPM mode, which implies that the disc that "The Ol' Jitterbug" is etched on is a 33 RPM disc and that Kris is speeding up the song by setting the wrong turntable speed on the gramophone.
- The song is more muffled in the in-game file compared to the soundtrack.