People have been posting pictures of themselves packed into music cases after reports fugitive businessman Carlos Ghosn escaped from Japan in a similar way.
Yamaha has warned against trying to squeeze into its music instrument cases after images of people doing the "Carlos Ghosn challenge" spread online.
The fugitive businessman fled to Lebanon from Japan at the end of last year but has declined to reveal how he managed to escape.
One of his lawyers told reporters following his disappearance that his legal team had possession of all three of Ghosn's passports and that he didn't know how he fled the country.
The former Nissan and Renault boss faced prosecution in Japan for allegedly misusing company funds and misstating his income.
Amid reports that Ghosn had concealed himself in a large speaker box that was too large to fit through airport X-ray scanners, Yamaha issued a warning.
“We won’t mention the reason, but there have been many tweets about climbing inside large musical instrument cases," said the Japanese company on Twitter. "A warning after any unfortunate accident would be too late, so we ask everyone not to try it.”
They were responding to social media posts that showed people trying to squeeze into musical instrument cases.