The Opera Company of Brooklyn recently had to cancel a benefit concert over its use of an electronic device called the Sinfonia.

The electronic music maker, which supposedly rivals the sounds of real instruments, is a bone of contention among performers, and the New York musicians union threatened to protest the event.

This isn’t the first time the keyboard has been at the center of controversy. According to The New York Times, the Sinfonia was an issue in last year’s Broadway strike. Manufacturer Realtime Music Solutions believes its product can replicate orchestral instruments exactly.

Local 802 of the American Federation of Musicians promised to protest the December 14th concert at CAMI Hall, where it said the opera company was “showcasing and promoting” the Sinfonia, the Times reported. The instrument was to accompany singers on Mozart’s “Magic Flute.”

Ronald Wilford, chairman of venue operator Columbia Artists Management, supposedly came down hard on the opera company. A lawyer for the opera, Edward Quigley, told the Times that Wilford contacted the group hours before the event, claiming the Sinfonia was to “take the place” of live musicians.

“You never informed us of your intentions to use CAMI Hall for such a purpose,” Wilford reportedly said. “CAMI Hall is for the use of musicians performing live music.”

According to Wilford, use of the hall was withdrawn because the Opera Company of Brooklyn did not have a contract with CAMI. Wilford disputed that, saying a contract was signed and fees were paid.

When asked for a comment, a spokeswoman for CAMI told Pollstar that the decision to cancel the concert was CAMI’s statement.