The 27-year-old's career is in jeopardy after he was accused of smashing a blood vial with a hammer during an out-of-competition dope test last year.
FINA agreed with Sun that testers failed to produce adequate identification or follow protocol, but the World Anti-Doping Agency (WADA) responded by taking the case to CAS.
"Misguided public opinion has distorted the facts," Sun, a hero to millions in China but derided as a "drugs cheat" by some of his rivals, wrote on social media.
"My training and my personal life have been greatly disturbed by this and it’s become intolerable."
Sun, a controversial character, was allowed to compete in the World Championships in South Korea in July, winning two golds but also becoming a focus of protests from other swimmers.
Writing on the Twitter-like Weibo, Sun said that he was looking forward to giving his account of what happened during the now-infamous doping test.
"There is something I can’t say, I can't make the truth public," he added on Weibo.
"But fortunately the surveillance cameras have recorded everything, otherwise I won’t be able to defend myself against irresponsible accusations."
A CAS hearing was originally scheduled for September, but is now unlikely to be before the end of October, CAS said earlier this month.