I don't know offhand of amps/receivers that offer "level trim" on various inputs but will mention this:
Remember that FM and TV are highly compressed to make them "louder" overall, while DVD is likely to offer a superior dynamic range (but will seem quieter overall). The real question is: Are the loud explosions on your DVDs as loud as the TV and FM?
I have a sign above my edit suite that says "Can we have everything louder than everything else?" which is a quote from Ian Anderson of Jethro Tull...evidently to their sound man. I keep the sign there because I have clients in here all the time that don't understand that a gunshot does NOT sound loud if it's mixed at the same level as dialog. (I mean this as an example...my corporate productions usually don't involve gunshots, though some have!)
I'm not insinuating that YOU don't understand dynamic range, I just mention the sign since I put myself on that topic!