MY 17 F-Type R: HELP! First of all, I have not had any exhaust software updates that intentionally mute the exhaust note and take away pops and crackles. A few days ago I noticed a more muted exhaust note (I ALWAYS run in sport/dynamic). I traced it to the exhaust baffles remaining party closed due to some sort of vacuum leak. I was able to reach in and manually open them all the way, and upon cold start this morning the exhaust sounded it's loud obnoxious normal self. I backed out of the the driveway and drove down the street...everything sounded normal. pops crackles and all...normal for about one minute, and then I heard the sound mute itself around 30 to 40%. (Not as muted if I were to turn off dynamic mode and close the baffles...but still muted). I was still in dynamic/sport, exhaust open etc. ARRRRGGGG!!! I thought maybe the valves partly closed again, but I pulled over, and with the engine running, could see that the valves were still fully open. HUH? OK...QUESTION: Why would it sound perfectly normal at start up, valves open, and then sound somewhat muted after a short distance (valves still open)? if there IS a disconnected vacuum hose, is there something else in the exhaust chain that would cause this behavior? Could it be a bad catalytic convertor? I'm obviously guessing. Something Is muting the sound when the car warms up (and the valves are fully open!) Again...I have had no software updates, and my last oil/maintenance appt was last January. My poor Jag is losing it's voice :-(