I have a co-worker who has a strong tendency to break into song whenever words people use in conversation remind him of a song lyric. This meant that several times a day he’d bust out with show tunes or other songs—right there in the office. (Unaccompanied). While his voice wasn’t terrible or anything..it did get a bit…disruptive in our otherwise quiet office environment filled with software geeks.
The only thing we could do was groan and tease him (gently) to finally break him of this habit.
It turns out this is how his family interacts (they’re like a scene out of ‘The Sound of Music’ at home apparently – each kid plays at least one instrument, too) ..so he didn’t realize it could be annoying in an office environment until we pointed it out.
If you can, jokingly and gently, point out to your coworker not everyone likes singing in the office.. then perhaps you can say something to your co-worker to discourage the singing…