My 2005 TL (Auto) with Navi has been in a dealer for about a week to fix a problem related to HFL and audio. Unfortunately, the service manager told me today that they had no clue how to fix it and they were waiting for reply from the Acura Techline. The problem started about a year ago. It begun with no audio occasionally after the car started. But the audio usually came back after I tweaked a few audio adjustment buttons. About two weeks ago, I noticed the HFL had no sound prompt after I pressed the HFL button, and there were no audio whatsoever. I took my car to the dealer and the service manager played with every button for about 2 minutes, the audio came back. The car behaved well for a few days, and audio and HFL stopped working again. Sometimes I actually could hear cracking noise when I pressed the HFL button. I took my car to the dealer last Tuesday to let them to find out what was wrong. I expected this problem was not easy to fix. But I am not sure it would take this long to find out what went wrong. If the car were not under warranty, I could probably fix the damn thing by now. Have anyone had similar problems like this? Any ideas or hints? The dealer gave me a MDX as a loaner. The MDX is nice, but it burns too much gas and after all it is not a TL.