The conversation began when David asked JJ what he knew about the housemates when he entered halfway through the series.
"Did you know Steve wasn't as big a favourite as we all thought he was?" David asked.
"No, I thought he would be here [in the final]," JJ replied. "But Sammy Pepper did, though."
The pair then agreed that Sam had known more than he let on during his time as a housemate.
"He knew everything," David said, as JJ confirmed that Sam had probably been on the website and seen everyone's pictures and biographies, among other information.
"He was wrong about John, though, wasn't he?" David continued, referring to Sam striking up an unlikely friendship with John James despite tension between himself and Josie.
"I'd rather have been like I am and not know that much, then to know everything," JJ said of his late entry into Big Brother.
JJ then confirmed that although he had seen parts of the programme's coverage on Big Brother's Little Brother, he hadn't watched many of the highlights shows so didn't feel he had come into the house at an advantage.