The Honolulu Liquor Commission today levied a $500 fine on a Waikiki karaoke bar for noise and imposed fines on three other liquor establishments for serving alcohol to people under 21.

According to the violation, Wang Chung’s permitted entertainment that disrupted the “peace and quiet” of the neighborhood on Dec. 2.

A city prosecutor said investigators responding to a noise complaint saw a group of people laughing and talking loudly outside and when the doors were opened, could hear loud music from 75 feet away.

Before the Dec. 2 violation, the bar had four noise complaints on Nov. 12, 24, 29, and Sept. 25, 2009, the prosecutor said.

It was the first violation for the small, 200-square-foot bar, which is nestled in a cove next to an apartment building.

The commission also fined Big City Diner $2,000 for serving liquor to a minor in November, suspended $500 of the fine for the restaurant’s efforts to curb underage drinking and allowed the business to use $200 of its fine to buy a license scanner.

The commission also issued $1,000 fines to two separate establishments — Ku’ai Market and Accents — for selling liquor to underaged customers late last year. All three violations were discovered during joint police and liquor commission investigations, using an underage decoy.