The band released their album teaser last week, and eagle-eyed fans noticed something in particular. While the avatars of the boys are performing, a truck passes by on the right with the letters 'B IU'. The B is in the same font as Busker Busker's logo, so some fans have hypothesized that IU participated in the band's album!

SEE ALSO: Busker Busker turn into cartoons for their 2nd album teaser

Others aren't so sure about the featuring, especially because the two artists' promotional periods will be overlapping.�

Watch the teaser again below. The truck passes by from about 0:08 to 0:12.�

Do you think the fans may be onto something, or are they looking too deep into something that's not there?