It’s not clear how the conservative talk show host affected Dial Global — the radio programming company that merged last year with Westwood One. (Limbaugh is syndicated by Clear Channel.) But Dial says in an SEC filing that “advertisers’ response to controversial statements by a certain nationally syndicated talk radio personality in March 2012″ contributed to financial woes that raise “substantial doubt about the Company’s ability to continue as a going concern.” The March date coincides with an advertiser boycott of Limbaugh following his attacks on Georgetown University law student Sandra Fluke, who urged Congress to require employer health insurance plans to cover contraception.

But Limbaugh appears to be the least of Dial’s problems: Its stock is down nearly 77% today, to about 47 cents, after it said that it may not be able to meet its debt covenants and will voluntarily leave NASDAQ to just trade over the counter. The company reported a Q3 net loss of $71.2M, up from a $5.2M loss in the period last year, on revenues of $58.2M, +132.7%. In addition to the Limbaugh controversy, Dial attributes its losses to late cancellations of ad buys (which it says were due to “the election and renewed economic uncertainty”), and growing competition from digital ad platforms and major radio companies.

Private equity firms Oaktree Capital Management and The Gores Group own about 90% of Dial’s stock. It syndicates music, news, sports, events (including the Grammys and the Academy of Country Music Awards), and talk shows featuring Charles Osgood, Dennis Miller, Ed Schultz, Stephanie Miller and Clark Howard.