I hate to keep beating a dead horse, but whip-crack! About 2 months ago I had a Magnaflow 5"x8" muffler, I think #12229, installed on our 08 Denali XL. I also did a resonator delete with some off the shelve brand dual tip side exit set up. I definitely noticed the drone inside the cab at mid range rpm's but thought I'd get used to it. After a looong road trip, it got really annoying. I called the shop who installed everything and he suggested adding a straight though design resonator between the engine and the muffler to cancel out some of the drone, cost about $120 installed. I still want the truck to be loud and perform well, but I gotta fix the drone. Should I just add the resonator or swap out the muffler for a different size or different brand? Let the debate begin.....again.