why my Q45 is louder

[blacktea]

I know this is difficult to answer but I am not sure where to start. My q45 is louder after parking for a while. I don't drive much, less than 2000 mi a year. It's hard explain what the sound like, probably it's loud like a boat. where should I start to look at ? Will tune up at auto service help to fix the problem ? I already change spark plugs and pcv values. Thanks.

[OwnerCS]

Does it sound like a loud exhaust noise coming up in the engine compartment?

[blacktea]

Thanks ownerCS for trying to help. I got it fix today for $115. The pipe under passenger was damage. They cut that section and put a new one in. Now it's quiet like before.

[thehacker3]

Does it sound like a loud exhaust noise coming up in the engine compartment?

Mine kinda sounds like that. It's an '05. Any ideas what the problem is? It doesn't really bother me, but it would be nice to know.