Kyodo news service lives up to its reputation:
Monkey in Walkman commercial dies at 29
KOFU — An award-winning monkey who held a Sony Corp Walkman player in his hand, wore a headset and stood as if captivated by music in a TV commercial aired in the late 1980s died of old age in Kumamoto Prefecture on Sunday.
The monkey, known by its stage name Choromatsu, was 29, said to be equivalent to roughly 100 years old for a human, according to a person involved in running the monkey troupe he belonged to.
I guess the troupe owner didn't want to go on record with this potentially explosive revelation.