After the Alpine Drop Track in career mode, both Tag's Crew Chief and mother starts to complain that his kart's Boom Box is somehow actually taking major damage, when it is designed to be indestructible. The Chief also says that one hit to the right spot will completely destroy the Boom Box and cause Tag to be unable to race (probably because if his kart gets hit without a Boom Box, it will completely destroy the kart and render Tag in an even worse situation).
This prediction actually becomes true after the Range Tour. Both Tag's kart and it's Boom Box is destroyed from a bomb planted by Uncle Richard from Conservative Motors, which causes Tag to be unable to race and be forced to sign Uncle Richard's contract to be able to race again. The same explosion also knocked out the Chief and put him in a coma, but his eyes are still open regardless. This coma also prevented him from stoping Tag from signing the contract.