Justin Timberlake Apologizes For Beatboxing Phase, Says It May Happen Again

Justin Timberlake is telling fans he's sorry for his beatboxing era ... while also not promising the spirit won't overtake him again.

Here's the deal ... Hannah Young -- an influencer with an encyclopedic knowledge of all things pop culture who goes by "uhhuhhannah" on Instagram -- posted a video about the strange moment in JT's career where he seemed to beatbox every time someone put a mic in front of him.

Hannah says it's not just his fault either ... because no matter how many "boots and cats" he threw into the microphone, she says his fans back in the day were always rocking with him -- swooning over his instrumental imitations.

The post blew up on social media ... so much so that even Justin saw it -- and replied.

Justin says he often looks back on that era and can't answer why he felt so compelled to lay down a beat.

JT says ... "I don't know how to apologize enough for whatever those ambitions were. Too many boots. Too many cats. I hope you can forgive me."

Thing is ... Justin says that, despite his deepest apologies, he can't promise it won't happen again.