Iz*One have postponed the release of their new album after the 12-member Korean girl group were swept up in the latest storm engulfing the K-pop industry.
This time, the controversy is over vote-tampering by the producers of Korean TV shows to unearth new singing talent.
Viewers were told that they had the final say in the make-up of new K-pop groups.
But evidence has now surfaced that the line-ups of X1, I.O.I and Iz*One were already finalised by the producers before the viewers cast their votes.
The trainees had appeared in shows called Produce X 101 and Produce 48.
Producer Ahn Joon-young, who admitted to the vote-rigging, has been referred to the prosecutors.
They said he and another producer, Kim Yong-bum, had their own favourite trainees whom they wanted to assign to various new K-pop groups.
The public voting was actually a sham, and the people behind the shows even took a cut of the money that was spent by the viewers when they voted.
The producers were hauled up when some viewers raised questions over the selection of trainees, wondering why certain names, deemed to be hot favourites, did not make the final cut.
According to documents detailing the alleged offences, Ahn and Kim met on July 17 last year to confirm the 11 trainees who would enter the industry as X1, after the finale of Produce X 101.
The two allegedly manipulated the online votes from viewers to suit their own purpose.
Similarly, the 12 members of Iz*One were also pre-decided before Produce 48 viewers voted.
Ahn and Kim are said to have made their final Iz*One choices in a meeting in August last year.
One trainee was also allegedly removed from the final 11-strong Wanna One line-up, in favour of another, by Ahn in June 2017.
Four agencies are said to have paid money to Ahn to ensure that their trainees, whom they had sent to the audition shows, would still be left standing in the end.
The news have upset K-pop fans who were already reeling from other disclosures in the K-pop scandal that broke out in January, with artists pulled up for misbehaviour from sexual assaults to drug-taking.
Two singers, Jung Joon-young and Choi Jong-hoon, recently received jail sentences of six years and five years respectively for raping a woman in 2016.
But some netizens have urged fans to refrain from abandoning their support for the X1, I.O.I, Wanna One and Iz*One singers.
"All we can do now is to give a hug to the trainees who appeared (on the shows and failed to be picked).
"You can't throw stones at any member (who made it).
"They didn't take away an opportunity from someone else. They are all victims (of the vote-rigging)," one person posted online.