The founder of top South Korean talent agency YG Entertainment, Yang Hyun-suk, was forced to step down over criticism that it had not managed its artists well.
Two singers, BigBang's Seungri and FT Island's Choi Jong-hoon, were booked by the authorities for offences from embezzlement of funds to bribery for covering up drink-driving.
Now, there is talk over whether YG has managed the money earned by its artists in a professional manner.
Yang, who is being investigated for gambling, is said to have used the proceeds from YG artists' shows in the United States to fund his Las Vegas casino outings.
The Korean media reported that the Federal Bureau of Investigation in the United States is helping the Korean investigators to gather evidence from the casino.
A source told media outlet Channel A that the police also want to find out whether Yang tapped company funds too.
Earlier reports said he lost more than US$500,000 (S$693,000) in total when he visited the casino 11 times in 2017 and last year.
The police are also checking out reports that Yang could have gambled in other countries too.
Seungri is also said to have lost more than US$1 million in a Las Vegas casino.