I 2nd that motion.

Are you sure that it was simply a case of a nut coming loose? If yes - I meant no disrespect. I've had a couple of OS46 AXmufflers separate in flight - neither was because the nut came loose. In both cases the center bolt broke. Some have advised using some stainless steel wire to create a "safety wire" loop that will hold the two pieces together in case the bolt breaks. Some have replaced the center bolt with threaded stock with nuts on both ends using Loctite on both.Some use hi-temp RTV to create a non-hardening gasket at the seam of the muffler pieces as well as at the bolt head and the bolt's nut.

Macs makes a nice 1-piece muffler (not their tuned pipe) for many engines. I replaced my OS46 AXOEMunit with a Macs.