Financial difficulties are continuing at the largest operator of radio stations in the U.S. and owner of several Honolulu stations, San Antonio-based iHeartMedia Inc.

In May iHeartMedia extended for a fifth time its offer to refinance about $14 billion of debt, an indication that the company is having difficulty finding investors.

In the company’s first-quarter earnings released earlier that month, iHeartMedia said there is “substantial doubt as to our ability to continue as a going concern.” The company said the statement was prompted by doubts about refinancing its debt and meeting its forecast results.

In Honolulu iHeartMedia employs 60 people and owns seven stations: KSSK Radio, Island 98.5, Star 101.9, 93.9 The Beat, KHVH News Radio 830, Fox Sports 990 Hawaii and 99.1 JAMZ Hawaii.

Representatives for iHeartMedia did not respond to questions about how the parent company’s financial situation might affect Hawaii stations.

The broadcast radio and entertainment provider has been struggling with the debt since 2008. Formerly CC Media Holdings, iHeartMedia faces $20 billion in debt it took on as part of a $24 billion leveraged buyout of Clear Channel Communications Inc. by private-equity firms Thomas H. Lee Partners and Bain Capital. In 2014 CC Media changed its name to iHeartMedia.

The day after iHeartMedia announced the extension of its refi offer, iHeart stock closed down 44 cents, or 20 percent, at $1.75. On Thursday the company’s stock closed at $1.89.