Mouse music

I had drifted off while reading, taking a nap because I’m feeling not 100% today, when I realised I was hearing music. Had I left the stereo on? No. Was the neighbor playing their good jazz music (their living room is one thin wall away from our bedroom)? No…
This was the Mickey Mouse Club theme song, tinkled out in loud, electronic tones. As I identified it, it morphed into the “yaki imo” truck’s traditional Japanese wail. The sweet potato truck drove slowly through the neighborhood and I didn’t hear any more mouse music.
I know our potato vendor doesn’t deviate from his usual tape loop. Where was the other music coming from?