LATEST: Jessica Simpson is desperately battling throat problems as she prepares to launch her new album, but has refused to cancel an appearance on MTV's TRL, which is hosted by ex-husband Nick Lachey's new girlfriend VANESSA MINNILLO. The pop star is in New York City to promote her new album A PUBLIC AFFAIR and has already cancelled appearances on US breakfast show TODAY and LATE SHOW WITH DAVID LETTERMAN. Simpson had a slew of media interviews planned and cancelled all of them - except TRL. Although she won't sing on the show, she will make a special guest appearance to promote the album. Simpson's representative ROB SHUTER tells American publication People, "Jessica has lost her voice on the eve of her album release. "We hope she can recover. The timing could not have been worse." Simpson appeared on TRL in July (06) to debut the video for A Public Affair and Minnillo was noticeably absent. A source close to Simpson says the singer visited doctors on Monday (28AUG06), saying, "If she does not observe vocal rest, she could lose her voice forever." The singer's roller-skating record release party is tonight (29AUG06) at the Roxy, but Simpson has been strictly forbidden from speaking.