The Batmobile is equipped with numerous gadgets that help the Dark Knight fight crime. One of the gadgets is the Bat radio. The Batmobile radio has made several appearances in the comics since its introduction in Detective Comics #92 and later appearing in Detective Comics #449 (all the way through the movies, animated series and present comic books). The radio was primarily used to contact the police (esp. Commissioner Gordon), pick broadcasting signals from nearby vehicles and most importantly, be in continuous connection with the Bat-computer in the Bat-cave.
Source: Detective Comics #92
Source: Detective Comics #449
Every other gadget fit into the Batmobile has its own purpose. And the music player seemed quite off-character to me. Because Batman doesn't seem the type who would play music while fighting crime and chasing super-villains (Except if you count the Lego Batman who actually has a playlist for every situation).
However, in Justice League: The Animated series (Season 2 Episode 5-6: Only a Dream), when Doctor Destiny is taking down the league members one-by-one, Batman is on his way trying to stop him. To avoid falling off to sleep, Batman breaks his windshield, and starts playing loud music (on his Bat-music-player) in the Batmobile.
So, has the Bat-music-player made any comic books appearances?