The US Justice Department is reported to be examining Apple's tactics in the market for digital music in a preliminary competition inquiry.
The New York Times, citing 'several people briefed on the conversations', said Justice Department staff members had talked to music labels and internet music companies as part of the inquiry, which it said was 'in its early stages'.
The Times said the conversations have revolved broadly around the dynamics of selling music online.
Besides music, Apple sells television shows, films and applications for its iPhone, iPod Touch and iPad through the online iTunes store it opened in 2003.
The Times said investigators had asked in particular about allegations that Apple used its dominant market position to persuade music labels to refuse to give online retailer Amazon exclusive access to music about to be released.
Billboard magazine reported in March that Amazon had asked music labels to give it the exclusive right to sell certain songs for one day before they went on sale more widely.
Representatives of Apple's iTunes music service asked the music labels not to participate in Amazon's promotion and punished those that did by withdrawing marketing support for those songs on iTunes, according to Billboard.
The Times, citing figures from marketing consultancy NPD Group, noted that Apple is the largest seller of online music in the US with a 69% share of the market followed by Amazon with 8%.
