Saunders, considered one of the top tight ends in the country, is close friends with Tar Heels defensive end Marvin Austin, who was also recently questioned by investigators.
On Thursday, a source said that UNC football players -- including Austin -- were being interviewed by the NCAA this week and asked questions about agents and whether anyone had received gifts or extra benefits.
The source also said that the NCAA's questions to players were intended to "make sure no Reggie Bush stuff is going on."
"I'm not really sure what's going on right now in terms of who's in trouble and how much," Saunders said Sunday.
Another source who has visited with Saunders said Sunday the NCAA is interested in time Saunders spent with Austin in South Florida this spring and who paid for hotel rooms and travel.
University of South Carolina athletics director Eric Hyman issued a statement Sunday acknowledging the NCAA's inquiry.
"The NCAA has been in contact with us regarding a possible rules violation in one of our programs," the statement said. "We have and will continue to cooperate fully with their inquiry. We have confidence in our compliance program and will work with the NCAA to bring this matter to a resolution in a timely fashion."
Coach Steve Spurrier told The (Columbia) State that he has no knowledge of Saunders breaking any rules.
"All I know is they had talked to him, and talked to some players at North Carolina. That's all I know," Spurrier told the paper. "Whatever comes [of it], we'll just have to wait and see.
"We're not going to look the other way like possibly Southern California did," Spurrier continued. "We're going to abide by the rules."
Calls and messages from The Associated Press to Spurrier, returning from a celebrity golf tournament in Nevada, were not immediately returned. Calls to Saunders' father, Barry, a news columnist at a Raleigh, N.C., newspaper, also were not returned.
The investigation began with a phone call from the NCAA, North Carolina athletic director Dick Baddour said Thursday, though he declined to say when the call came or when investigators had visited the Chapel Hill campus.
A second source said Thursday that the NCAA asked all of UNC's projected NFL draft picks, many of whom elected to stay in Chapel Hill, to provide phone records so investigators could see which agents they had spoken with.
The players were also asked who paid for the travel, who paid their rent and which agents they had met with and when, according to the second source.
Austin recently tweeted about a trip to Miami.
Joe Schad is a college football reporter for ESPN. Information from The Associated Press was used in this report.