Beazer Homes USA Inc. shares fell as much as 13 percent after the homebuilder received notices of default from a bondholders’ group for failing to file a quarterly report with regulators.

The seller of homes for first-time buyers said the notices have no merit and it’s not in default. The notices from U.S. Bank National Association, a trustee for debt investors, cover notes due 2011 to 2016, Atlanta-based Beazer said today in a statement.

The FBI is investigating Beazer for potential fraud and the Securities and Exchange Commission has opened a probe of the company. Beazer said it hasn’t filed the financial report on time because of an internal accounting investigation.

ADDED from Forbes.

Beazer has already been plagued by bankruptcy rumors, causing the stock to plunge as much as 40% on Aug .1. (See ” Beazer Shares Punished By Rumors”) The company dismissed the rumors as ” scurrilous and unfounded.” But on Aug. 24 Moody’s Investors Service cut Beazer’s credit ratings because of concerns over investigations into the company’s mortgage business and its failure to file its third quarter financial reports.

Sounds like Ameriquest or New Century last year.