Weird Sound Under Throttle

[Notorious6.0]

Have an 03 6.0, couple weeks ago had IC(CAC?) tube boots, turbo, and EGR replaced. Truck did excellent until last night. Driving up a hill, on the throttle and hear a weird noise like the IC(CAC?) boot blowing off but not as loud when that happened before. Gave it gas to see if boost was still there and it was, however, now at about half throttle there is a low moan.(has a kind of high -pitched sound to it if that makes sense) It doesn't do it low throttle or full throttle, seems to be around half throttle. Didn't seem to lose any power but the moan is annoying. All the boots are ok. What could this be? Should I take it back to the dealer?(it's still under warranty) Any suggestions? Thanks.
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