Occasional Strange Noise while Shifting

I was driving my 2007 F430 F1 this afternoon, while enjoying a nice ride on a sunny day, going up the mountain I geared down from 4th to 3rd so I can enjoy the sound of the engine as I made the turns, the car made this strange noise, it felt like s sheets of metal smashing each other, it lasted for 1 or 2 seconds. The car continued to drive fine, no alarms came on, all pressures were normal. I continued driving for 30 more minutes and then it did it again but much lesser noise than the first time, going from 2nd to 3rd. I drove for another 30 minutes and it did not do it.

When I got home, I put the car in the garage and few hours later I checked underneath it, no sign of oil drops or any damage.

I appreciate any help or guidance from the members.

 

Thank you for the reply, the car has 14,500 miles. If it is a 3rd gear syncro issue, is it expensive to fix? Can I drive it to the dealership?

Can this noise be the headers? My dreaded fear.....

 

Thank you Rifledriver, if it is a syncro issue, would it do it all the time or can it be occasional? The reason I am asking is that it did it only twice in about 2 hours drive although I shifted a lot to and from 3rd gear frequently to replicate the incident.

 

Is it very expensive to fix? Is there a lot of labor involved in fixing it? I am not mechanically savvy at all and will end up doing what the dealership says to do, so any advice on that front is appreciated.

 

Rifledriver, thank you for the support. Much Appreciated.