[dead ringer]

ok, let me start off by saying I am not that handy when working on cars...

2 weeks ago I discovered a leak & took to dealership. They found it was a bad seal in the transmission & I got the car back a week later on Friday. He mentioned they had to drop the transmission....
That same night I discovered another leak, took it back into the dealer the next morning ( ** at that time I didn't notice anything different, BUT I did swap in an AA filter from the stock before taking it back in the next morning** )... He called on monday and said they found another leak, not related to the first but who knows what could have happened during the first fix.... If anyone needs to know I am sure I can find the parts they replaced if it makes a difference

Got the car back yesterday so it was at the dealer 5 days, and last night/today it just sounds different, kinda like there is a leak, you can hear the engine a lot more (kinda raspy but not in a good way), its just louder where as before it was smoother. My question is would/could they have disconnected the exhaust and not replaced it back correctly (I have ACM test pipes), or anything else to make it sound differently? I highly doubt it, but could they have run any ECU changes?

thanks for any input